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The configurations of epidermal ridges in a human Acephalic monster.

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Depurtment of Anatonky, flw Tulane University of Louisiana
The accompanying description of epidermal ridge configurations in an Acephalus monobrachius is presented as the
second contribution to a projected series of studies devoted
to the configurations in developmental defects involving the
hands, feet, and digits. This paper follows a report covering
twenty cases of membranous and cutaneous syndactylism
(zygodactyly ) of the second and third t0es.l F urther material
now available comprises, especially, case6 of hyperdactylism,
high-grade syndactylism, and ectrodactylism. A separate
account of each variety i b desirable, in fact necessary, owing
to the diversity and extent of the material. I n a final paper
of the series the writer purposes to correlate the conclusions
derived from the several defects, also to extend and amplify
the survey of literature which was included in the introductory study.
The observation of developmental defects provides a
natural substitute f o r an experimental approach, which is not
feasible, to the problem of what factors govern the disposition
of ridges in patterns and patternless areas. It map be statad
hew, briefly, that the varying interpretations of ridge direction a r e grouped into two classes. According to the one,
emphasis is placed upon the facilitation of frictional and
' Cunimins, Harold, and Sicomo, Joseph. Plantar epidermal configurations in
low-grade syndaetylism (7ygoll:ictyly) of the sccoud and third tors.
vol. 25, no. 6 , 1923.
.inat. Hec.,
tactual functions subserved by the ridge arrangements, and
such arrangements a r e considered to be primary foci of evolution. An implication of a direct germinal provision for configurations, per se, is carried by this idea. On the otlicr hand,
the second interpretation explains the direction of ridges
simply on the basis of response to growth forces operating
during the fetal period of ridge differentiation. The writpr's
observations support the latter view.
u ' r E 11I A1
The monster here reported was presented by Dr. I?. R.
Towne, of Jackson, Michigan. I t was found, apparently after
a preservation of years, in the course of renovating a hospital
storage room. No label was attached to the specimen; therefore, its history cannot be stated. Since the specimen has not
been dissected, identification as a n omphalosite is based upon
external features only, and not upon the disclosure of an
acardiac condition connoting a co-twin or the known existence
of a co-twin. While it seems altogether probable that the
idmtification is (.orrect, note should be made of the f a d ~ l i a l
the purpose of the study does not require a diagnosis.
Omphalosites furnish material wliich is singularly adapted
to the rcyuirements of an investigation depending upon fortuitous and undesigned dcvelopmcntal abnormalities. A noteworthy advantage consists in their origin from germ plasm
which probably is normal, and which if abnormal certainly
cannot c a r q - specific gciininel deterniinants f o r tlie monstrous
productions or for their aberrant configurations. Morcover,
the diverse forms assumed by their estremities, when present,
afford an excellent test of correspondence between contours
and ridge directions. Another feature of patent value is their
fetal nature. As is well known, the characteristic and distinctly prominent palmar and plantar eminences of the early
normal human fetus become less and less prominent with
advancing development. Postnatally, some of them are entirely obliterated, while thosc which persist do not retain
their original forms. It is not believed that the elevations
described in this specimen have retained precisely their
earlier form and relative prominence. To the contrary, the
noriiial developmental history of such eminences probably is
repeated here, although opportunely interrupted at a time
when they still are distinguishable.
1)ES(‘ K I PTI 0s
The acephali, of which this specimen appears to be a representative example, are as a group characterized by the following external features? absence of head; usual absence of one
o r both upper extremities, and these imperfect if present;
fairly good development of trunk and lower extremities, although naturally imperfect ; frequent umbilical hernia ;
ventral median thoracic fissure ; general edema. The specimen, a male, is shown in figure 1, which illustrates its conformity to the above characterization. The aspect chosen for
the figure, a left-front view, fails to show the total absence of
any superficial indication of a right upper extremity. Edema
is indicated by numerous wrinkles, resulting from reduction
of the edema in preservation.
Left upper eictrewity
The left upper extremity is represented by a n appendage
3 em. in length, showing both phoconiely anti ectrodactplism
(fig. 1). Its outer and inner aspects are designated, respectively, as dorsal and palmar surfaces in conformity with the
presence of a nail and ridge-bearing epidermis. Indicating
tlic directions toward whicli they face, the remaining surfaces
are named ‘front’ and ‘back.’
Distally, the extremity bears a short, bluntly rounded
process 7 mm. wide (figs. 1 and 2), limited from the proximal
and broader portion of the extremity by a slight constriction.
A very small nail is present on the dorsal aspect of this
‘Hirst, B. C., am1 Picrsol. Grorge A., Human ~nonstrositics,P a r t ITT.
(lclpliia, 1892.
process, which is the only digit present. Viewed from the
distal end (fig. 4), the digit is almost round, but there is an
asymmetry of contour which throws its maximum dorsopalmar dimension toward the front margin. A similar but
less marked asymmetrv is evident dorsally, where a slight
Fig. 1 Acephalus monobrachius, left-front view, x 1/2. Kotc the rudimentary
left upper extremity, representing one digit and a palm attached directly to the
shoulder, the maldevelopinent and talipes varus of the feet, umbilical hernia,
ventral median thoracic fissure, absence of head (the irregular prominence sur
mounting the thorax may represent a n abortive head formation). The numerous
wrinklcs result from reduction of the edema in preservation.
eminence is situated toward the back margin. The dorsal
slope of the distal end of the digit shares a small part of this
eminence, but the elevation diminishes in its distal extent.
The digital configurations are to be described under the
following heads: 1) apical pattern, 2) accessory distal configuration, and, 3) transverse ridges proximal to the apical
1. The apical pattern is a whorl, as shown in figure 2. No
additional description is necessary. However, attention is
called to its asymmetry in form and position. The core of the
whorl is situated upon the greatest eminence of the ball, which,
as noted above, deviates toward the front margin.
Fig. 2 Palmar surface of the left upper extremity, showing eonfigurations
of the single finger and palm. The head of the palmar loop, which extends upon
the front margin and dorsum of the palm, is shown without the front boundary
of the palm, in the conventional manner of representing patterns on upturned
surfaces. This and the succeeding illustrations of configurations do not purport
t o possess the precise accuracy which obtains in tracings from actual prints.
The study of these configurations was made, necessarily, on the specimen itself,
under low magnification. While precautions were followed, including repeated
checking of the original drawings, to ensure as accurate a reproduction as
possible, the lines do not represent the exact courses of individual ridges, but
rather, the general courses of ridges within the area.
Fig. 3 Dorsal aspect of the finger, showing atypical configurations. The
nail bed is shown in solid black.
Fig. 4 Outline of the ball of the finger, as viewed from the distal end.
Note the asymmetry of the apical pad, displacement toward the front margin,
left in the figure. Also observe the slight elevation of the dorsal surface,
toward the back margin, right in the figure. The apical and accessory distal
configurations are borne upon the respective elevations.
Fig. 5 Outline of the mid-portion of the palm, as viewed from the distal end.
Note that its greatest dorso-palmnr dimension is situated toward the front
margin, left in the figure. The greatest elevation of the palmar surface marks
the point, shown in figure 2, where arciform ridges of the palm course around
the prmimal radiant of the p21ni:ir triradius.
2. I n figure 3 a r e shown the dispositions of ridges which
occur upon the dorsum of the digit and the slope of its distal
end. Especially notewortliy is the presence of a small loop, its
core being situated upon the maximum elevation of the small
dorsal eminence noted above.
3. Transverse ridges occupy the interval between the apical
pattern and a triradius of tlic palm (fig. 2). Their ends C O U ~ S ( '
dorsally over the front and back surfaces, thus presenting no
dcpartures from the normal.
The remaining part of the extremity, the palm, is pad-like
in shape, compressed in tlie dorso-palrnar dimension, and
attached directly to the trunk by a constricted pedicle. There
is marked asymmetry in its transverse outline (fig. 5), its
iimsimum tliicdmc ss Iwiiig toward t l ~ efront margin. Located
in about tlie mid-portion of the front margin, and extended
upon tlie dorsum, tlwrci is a lorn hut extensive elevation, not
shown in the figures.
d conspicuous feature of the palmar configurations is a
large loop. The head of the loop coincides with the front and
dorsal cllcvation just mmtioned. The writer hesitates to
Iiomologizc this pattei,i with any component of the normal
palmar configurations. F o r this and other features of the
palm see figure 2. The presence of a single (digitall) triradius is to be noted; it is determined distally by transverse
tligital ridges and proximally b y arciform palmar ridges
coursing in two directions. Thc most proximal of these arciform ridges form a complete arch, the apex of which marks
tlic greatest elevatioii of the palmar surface.
Lozuct. cxtl-ernities
Both lower cstr~iiiitics cxliibit marked talipcs Tarus
(fig. 1) and defective digital development (figs. 6 and 7).
Since the identities of certain digits a r e questionable, reference will be made to them as A, B, C, and TI, in order, beginning on the tibia1 side.
Rigkt (fig. 6)
Only four digits are present (ectrodactylism), and two of
them are joined by skin bands (cutaneous syndactylism) .
There is a possibility that C and D are not digits 4 and 5, as
they appear to be, but are the result of duplication of either
4 or 5 with coexisting syndactylism.
Fig. 6 Plantar configmations of the right foot. Note the absence of one
digit, the cutaneous syndactylism of C and D, and the nonnal contours of A
.iiitl R The configurations of A and B, as well as the neighboring region of thc
sole, are not atypical, while the ridge directions of C and D, also of the adjacent
sole area, exhibit variants of a type previously found to be associated with lowgradc syndactylism.
Fig. 7 Plantar eonfigurntions of the left foot. Observe the absence of one
digit, the cutaneous syndactylism of A and B, and the atypical forms of C and
D, especially the latter. Note the atypical ridge directions of C and D and of
the sole. Compare thc digital configurations of A and B with those of C and
D of the right foot; the variants are of the same fundamental typc, differing
only in the degree of approximation of the apical patterns.
A and B are typical in form, as compared with the toes of
late normal fetuses, Each of these digits is bulbous distally,
in that the plantar surface of each is decidedly swollen into
an apical pad. Their configurations are not atypical. C and
D show certain features which are worthy of especial mention.
The apical pattern of D, a fibular loop, is displaced laterally
and distally, lying upon a prominent elevation of the latero
distal surface of the digit. Apart from this deviation, the
configurations are fundamentally like those of an adult
syndactyl, case 202, described and illustrated in the previous
The sole is wrinkled, rendering a determination of its
original contours impossible. Distally, the sole shows a hallucal pattern of a common type, an open field first interdigital
pattern, also of a common type, and an open field related to
C and D with ridges opening to the fibular margin. The lastnamed condition, associated with the absence of a critical
digital triradius, is of syndactylous significance. The entire
proximal portion of tlie sole is covered with parallel ridges
which course approximately transversely,' except for a very
small hypothenar loop lying upon the fibular border of
the sole.
Left (fig. 7 )
Only four digits are present (ectrodactylism) ; two of them
are joined by skin bands (cutaneous syndactylism) ; and one
is distinctly abnormal in form (perodactylism, in a strict
The skin bands which unite A and B are not so extensive
as to fuse the digits to their very ends. Aside from their
union, these digits are normal in form, and their configurations show only such departures as have been noted in digital
fusions. C, while isolated, is rather atypical; its distal end is
attenuated and bluntly pointed, with no suggestion of the
bulbous appearance which arises from the presence of a
normal apical pad. I t s apical configuration is a simple arch,
only one limb of the arch being located on the plantar surface;
the other limb is extended over the tibia1 side and dorsum.
The apex of the arch is related to the bluntly pointed end of
the digit. D, the only toe of either foot which does not bear
a nail, is sharply pointed and thus has no resemblance to a
normal digit at any stage of development. The ridges on its
plantar surface course in a direction which is oblique t o the
long axis of the digit. At the extreme distal end, and extend-
ing slightly upon tlie dorsum, there is the core of a whorl, not
shown in figure 7. Ridges on the plantar surface are gently
arciform, in accommodation t o tlie rounded surface. If these
arcs were extended hypothetically around the dorsum the
result would be a complete whorl, its core actually present
upon the apex of this sharply conical elevation.
The sole, which is not wrinkled as in the right foot, is subcylindrical, convex from side to side. Excepting for the loop
which probably represents a hallucal pattern, the sole is
covered with parallel ridges ; these ridges course practically
transversely across the tread area and turn vertically upon
the upturned ridge-bearing area of the tibia1 and fibular margins. The ridges which occupy the digital area region are
wider apart, as if from distension.
The palmar and plantar surfaces of the monster exhibit
structurally normal epidermal ridges, with rows of sweat
pores. I n only one relatively small area, the digital area
region of the left foot, do these ridges exhibit evidence of
irregularities arising subsequent to their histological differentiation. Since the alteration consists of a widening of the
intervals between ridges, it is suggested that the epidermis
may have been extended in the long axis of the foot by subjacent edema, or perhaps by a localized overgrowth in this
region. Elsewhere, the interrelationships of the ridges to
each other and their adaptation to the surfaces are perfect.
This circumstance indicates the existence, a s in the normal,
of a mutual correlation in the growth of surfaces and the
differentiation and growth of the ridges which they bear.
In organizing the descriptive matter on the directions of
ridges, two headings are suggested by the aim of the study:
1) ridge directions which can be correlated with contour, and,
2 ) ridge directions which cannot be so correlated.
1. The first head is divided naturally into: A) patterns
which are typical, that is t o say, patterns which are similar
in forni and position t o those in the normal; B) atypical patterns of syndactylous significance, and, C) other atypical
A. The digital configurations, including apical patterns and
basal transverse ridges of the finger and digits A and B of
the right foot, are typical. It will be recalled that each of
these digits has an apical pad, upon which the apical pattern
is situated. I n the case of the finger it is possible to further
correlate an asymmetry of the pad with asymmetry of the
pattern. In each case the basal transverse ridges are related
to the more constrictcd part of the digit, the region whic~11
is convex from side t o side. It is apparent, then, that typical
configurations in the instances cited are concurrent with
normal form o r contour of the digits.
B. Of the syndactyl variants, little need be said, inasmuch
as they have been discussed previously. Attention is called
to the fact that the adult material includes cases in which toes
2 and 3 are joined, with only occasional and slight involvement of 4. I n such cases there are pronounced ridge cleviations of the neighboring interdigital areas, when these arc
open fields, together with the obliteration of critical digital
triradii. Significantly, the right foot of the monster, with
syndactyl toes C and D, shows a like ridge deviation and loss
of a triradius in the axis of these digits. This finding verifies
a conclusion previously stated, namely, that the variants of
interdigital areas are a proximal expression of syndactylism.
-\berrant configurations of the syndactyl digits, C' and 1) of
the riglit foot and A and B of the left, require no particular
niention, since they are essentially like those already described. Exception must be made, however, of the displaced
apical pattern of D-a variation which is probably genetically
independent of the digital union; this mill be noted under the
nest heading.
C. Other atypical patterns are of prime interest, since for
each of them, as pointed o u t above, it is possible to distinquish a dcfinite correspondence between contonr and ridge
direction. The following configurations are included : u ) the
accessory distal configuration of the finger; b ) the palmar
pattern; c ) the displaced apical pattern of digit D of the right
foot; d and e) the generally abnormal configurations of digits
C and I> of the left foot, and, f ) the transverse direction of
ridges over the left sole, associated with total absence of three
interdigital patterns.
2. No significance is attached to the failure to ascertain a
correspondence between contours and configurations in two
locations, namely, the entire right sole and the hallucal region
of the left. I n explanation of the first instance it may be
repeated that the riglit sole is extensively wrinkled; while this
distortion does not prevent the observation of configurations,
it serves t o obscure and even obliterate the original contours.
The apparent lack of a pad related t o the hallucal pattern of
the left sole may be due, possibly, to the diminution of a
previously existing eminence to a degree where it has become
indistinguishably elevated above the relatively large sole area
with which comparison necessari1;- is made.
The data assembled above admit tlic following propositions :
1) A monster possessing varied defects of the extremities
exhibits typical ridge differentiation of the palmar and
plantar epidermis. To surface inspection, these ridges are
normal and are, moreover, arranged in configurations, inchiding loops, open fields, etc., all of them equivalent in their
forms of surface sculpturing to configurations in the normal.
2) However (see ‘Other atypical patterns, ’ above), certain
ones ( c and d ) which are apparently homologous t o particular
configurations in the normal are displaced from the normal
positions. Others (0,h l , and e ) appear to be supernumerary,
n o t represented by any corresponding configurations in the
normal. Yet another ( e ) shows a remarkable departure from
the typical ridge directions in the region involved; no plantar
surface hitherto recorded approaches so ncarly to a uniformly
transverse ridge direction as does the left sole. I n each of
the above instances thc atypical configuration is associated
with abnormal contours of the area occupied. 3 ) Several
variants (see ‘Atypical patterns of syndactylous significance, ’
above) a re attributed to the presence of digital fusions. 4)
Typical configurations do occur, the criterion of such being
the coincidence of normal situation and morphology. In
three digits it has been possible to establish the existence of
normal contours, coexistent with their typical configurations.
Unfavorable circumstances at the sites of other typical configurations have prevented a determination of their contours.
Upon passing to a consideration of the bearing of these
findings upon the qnestion of what factors determine configurations, the two divergent views should be recalled. Are
the several typical configurations present because certain
specific germinal determinants were for some reason immune
t o the developmental disturbance which involved the fetus as
a whole; and do the aberrant configurations owe their origin
to a vitiation of such determinants? O r are all the configurations, typical and atypical, elaborated through the operation
of other factors, with no provision for configurations, as such,
in the germ plasm?
I t appears likely, f o r the fetus probably is a n omphalosite,
that the germ was normal, the monstrous development being
initiated by vicious circumstances manifesting themselves
sonic time subsequent to fertilization. Granting normal germ
plasm, an hereditary transmission of the bizarre patterns is
precluded, since at least some of them have no known parallels
in the normal configurations. Although the germ may have
been abnormal, i t did not, naturally, carry predetermined
factors for the atypical configurations any more than it bore
detcirminants for the particular development of the monster.
I n either event, epidermal variants must be explained by a
disturbance of germinal configuration determinants or by the
admission of an immediate control of ridge dirwtion which
is not fisedly predetermined.
Each of the atypical configurations has been correlated with
variations of contour, and a definite correspondence between
the character of the contours and the type of configurations
is apparent. Moreover, there is a correspondence of normal
contours and typical configurations in three digits. These
consistent correspondences between contours and configurations, whether typical or atypical, indicate an orderly relationship between the two. Since contours of the palmar and
plantar surfaces, as elsewhere, are expressions of growth
complexes which vary locally in accordance with the form
being attained, the indication is that a control of ridge direction is exercised by phenomena of growth. It is to growth
forces, presumably those existing during the fetal period of
ridge differentiation, that the writer attributes the alignment
of epidermal ridges. Accordingly, there is no specific provision in the germ plasm for configurations. The epidermis in
its ridge-formative state is apparently plastic ; its potentialities of ridge direction are unlimited, although in the normal
course of events restricted in their expression by the range
of variation of growth forces.
The atypical configurations here described result from a
vicarious determination of ridge (direction. These configurations are elaborated through growth complexes which are
altogether foreign to the homologous areas of the normal
palmar and plantar surfaces. While the same mechanism of
growth forces is immediately responsible also f or the normal
configurations which occur, there is a directive element which
must not be overlooked. I refer t o a possibly directly
germinal regulation of contour, through which is mediated a
domination of the epidermis, hence admitting a secondary
r61e of the germ in the control of configurations. Such a
control is palpably not rigid and infallible, but is limited by
the labile nature of the mechanism.
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epidermal, acephalic, configuration, monster, human, ridges
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