CHAPTER XIII

GENERA 198

Type, meaning of 198

Law of frequency of error 198

Discussion of three elements in the loops on either thumb 200-207

Proportions of typical loops 209

The patterns are transmitted under conditions of panmixia, yet do not blend 209

Their genera are not due to selection; inference 210

Sports; variations 211

DESCRIPTION OF THE TABLES

PAGE

Summary of evidence in favour of finger marks being persistent 96

Interpolation of ridges 104

I. Percentage frequency of Arches, Loops, and Whorls on the different digits, as observed in the 5000 digits of 500 different persons 115

II. Distribution of the A. L. W. patterns on the corresponding digits of the two hands 116

III. Percentage frequency of Arches on the digits of the two hands 117

IV. Percentage frequency of Loops on the digits of the two hands 118

V. Percentage frequency of Whorls on the digits of the two hands 118

VI_a_. Percentage of cases in which the same class of pattern occurs in the same digits of the two hands 120

VI_b_. Percentage of cases in which the same class of pattern occurs in various couplets of different digits 120

VII. Couplets of fingers of different names in the same and in the opposite hands 121

VIII. Measures of relationship between the digits on a centesimal scale 129

IX. Index to 100 sets of finger prints 133

X. Number of different index-heads in 100 sets, according to the number of digits noted 136

XI. Number of entries under the same heads in 100 sets 139

XII. Index-headings under which more than 1 per cent of the sets were registered in 500 sets 140

XIII. Percentage of entries falling under a single head in 100, 300, and 500 sets 141

XIV. Number of different index-headings in 100 sets, according to the number of fingers in each set, and to the method of indexing 142

XV. Number of entries in 500 sets, each of the fore, middle, and ring-fingers only 146

XVI. Number of cases of various anthropometric data that severally fell in the three classes of large, medium, and small, when certain limiting values were adopted 159

XVII. Distribution of 500 sets of measures, each set consisting of five elements, into classes 160

XVIII. Number of the above sets that fell under the same headings 161

XIX. Further analysis of the two headings that contained the most numerous entries 162

XX. Observed random couplets 174

XXI. Calculated random couplets 174

XXII. Observed fraternal couplets 175

XXIII. Fraternal couplets--random, observed, and utmost feasible 176

XXIV. Three fingers of right hand in 150 fraternal couplets 181

XXV. Three fingers of right hand in 150 fraternal couplets-- random and observed 182

XXVI. Three fingers of right hand in 150 fraternal couplets-- resemblance measured on centesimal scale 182

XXVII. Twins 186

XXVIII. Children of like-patterned parents 188

XXIX. Paternal and maternal influence 190

XXX. Different races, percentage frequency of arches in fore-finger 194

XXXI. Distribution of number of ridges in AH, and of other measures in loops 203

XXXII. Ordinates to their schemes of distribution 204

XXXIII. Comparison of the above with calculated values 205

XXXIV. Proportions of a typical loop on the right and left thumbs respectively 209

DESCRIPTION OF THE PLATES

PAGE

I.--Fig. 1. Chinese coin with the symbol of the nail-mark of the Empress Wen-teh 25

Fig. 2. Order on a camp sutler by Mr. Gilbert Thompson, who used his finger print for the same purpose as the scroll-work in cheques, viz. to ensure the detection of erasures 27

II.--Fig. 3. Form of card used at my anthropometric laboratory for finger prints. It shows the places where they are severally impressed, whether dabbed or rolled (p. 40), and the hole by which they are secured in their box 145

Fig. 4. Small printing roller, used in the pocket apparatus, actual size. It may be covered either with india-rubber tubing or with roller composition 40

III.--Fig. 5. Diagram of the chief peculiarities of ridges, called here _minutiae_ (the scale is about eight times the natural size) 54

Fig. 6. The systems of ridges and the creases in the palm, indicated respectively by continuous and by dotted lines. Nos. 2, 3, 4, and 5 show variations in the boundaries of the systems of ridges, and places where smaller systems are sometimes interpolated 54

IV.--Fig. 7. The effects of scars and cuts on the ridges: _a_ is the result of a deep ulcer; _b_ the finger of a tailor (temporarily) scarred by the needle; _c_ the result of a deep cut 59

Fig. 8. Formation of the interspace: filled in (3) by a loop; in (4) by a scroll. The triangular plot or plots are indicated. In (1) there is no interspace, but a succession of arches are formed, gradually flattening into straight lines 67

V.--Fig. 9. Specimens of rolled thumb prints, of the natural size, in which the patterns have been outlined, p. 69, and on which lines have been drawn for orientation and charting 68

VI.--Fig. 10. Specimens of the outlines of the patterns on the ten digits of eight different persons, not selected but taken as they came. Its object is to give a general idea of the degree of their variety. The supply of ridges from the _inner_ (or thumb side) are coloured blue, those from the _outer_ are red (the scale is of the natural size) 70

VII.--Fig. 11. Standard patterns of Arches, together with some transitional forms, all with their names below 75

Fig. 12. As above, with respect to Loops 75

VIII.--Fig. 13. As above, with respect to Whorls 75

Fig. 14. Cores to Loops, which may consist either of single lines, here called _rods_, or of a recurved line or _staple_, while the ridges that immediately envelops them is called an _envelope_ 76

Fig. 15. Cores to Whorls 77

IX.--Fig. 15. Transitional patterns, enlarged three times, between Arches and either Loops or Whorls 79

X.--Fig. 16. Transitional patterns, as above, but between Loops and Whorls 79

XI.--Fig. 17. Diagram showing the nine genera formed by the corresponding combinations of the two letters by which they are expressed, each being _i_, _j_, or _o_ as the case may be. The first two diagrams are Arches, and not strictly patterns at all, but may with some justice be symbolised by _jj_ 80

Fig. 18. Ambiguities in minutiae, showing that certain details in them are not to be trusted, while others are 92

XII.--Fig. 19. The illustrations to Purkenje's _Commentatio_. They are photo-lithographed from the original, which is not clearly printed 86

XIII.--Fig. 20. Enlarged impressions of the same two fingers of V. H. Hd., first when a child of 2-1/2, and subsequently when a boy of 15 years of age. The lower pair are interesting from containing the unique case of failure of exact coincidence yet observed. It is marked A. The numerals indicate the correspondences 92

XIV.--Fig. 21. Contains portions on an enlarged scale of eight couplets of finger prints, the first print in each couplet having been taken many years before the second, as shown by the attached dates. The points of correspondence in each couplet are indicated by similar numerals 93

XV.--Fig. 22. The fore-finger of Sir W. J. Herschel as printed on two occasions, many years apart (enlarged scale). The numerals are here inserted on a plan that has the merit of clearness, but some of the lineations are thereby sacrificed 95

Fig. 23. Shows the periods of life over which the evidence of identity extends in Figs 20-22. [By an oversight, not perceived until too late for remedy, the bottom line begins at aet. 62 instead of 67] 97