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The integumentary patterns on the surface of the fingertips, palms, and soles.
The study of these patterns.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a branch of human morphology that studies the skin relief of the palms and soles, where the skin is covered with patterns of numerous ridges (papillary lines). Ridges and patterns are also found in simians, lemurs, and certain other mammals. The ridges are linear thickenings both within and on the surface of the epidermis. They begin to develop in the human fetus by the third month, but they do not appear on the surface of the skin until the 18th week. The papillary lines and patterns do not change with age, nor are they affected by surrounding conditions. They exhibit considerable individual variability; many of their particular features are transmitted by heredity.

The results of dermatoglyphics are therefore used widely in criminology, forensic medicine (in cases of disputed paternity), and clinical medicine (for early diagnosis of certain chromosomal diseases). Extensive study of skin patterns has revealed right-left, sexual, and territorial differences, which are used in anthropology, for example, to detect kinship between various human groups and to study the bilateral symmetry of the body. Skin patterns are also used in comparative anatomical studies of man and the primates and in anthropological genetics (familial and twin studies).


Gladkova, T. D. Kozhnye uzory kisti i stopy obez’ian i cheloveka. Moscow, 1966.
Cummins, H. and C. Midlo. Finger Prints, Palms, and Soles [2nd ed.]. New York, 1961.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
* A triradius found halfway in between these two positions (t) is found in 21% of the normal population.
To determine whether the position of axial triradius t, an abnormal neurodevelopmental marker, in schizophrenics non-responsive to treatment was different than those responsive to treatment.
Whether treatment resistance can be predicted by studying the axial triradius t and hence the ATD angle of an individual.
* a-b rc R--number of ridges between the triradii a and triradius b of the right hand.
* a-b rc L--number of ridges between triradii a and triradius b of the left-hand.
* b-c rc R--number of ridges between triradii b and triradius c of the right hand.
Atd Angle--is the angle subtended by lines drawn from digital triradius 'a' to axial triradius' t' and digital triradius' d' (Figure 2).
The opposite extremity is known as 'Open.' There is a single triradius. According to the side of opening of the curve loops may be ulnar loop or radial loop (Fig.
a-b ridge count: Triradius below the 2nd finger is marked.
A triradius is located at the meeting point of three opposing ridge systems.