676 CRIMINAL ANTHROPOLOGY. 



3Iaximum length of the head {skull). — The subject being seated, for 

 convenience, one point of the calipers is placed in the hollow above the 

 bridge of the nose, together while the other point is used to find the 

 greatest length at the back of the head. This should be done with 

 accuracy, and so that the length will be given exactly. If done with 

 care the true length can be obtained within 1 millimetre, which is about 

 one twenty-fifth part of an inch. It is admitted that the skull of man 

 developes but little, if any, after his maturity, 21 years of age. No 

 one j)ossesses any power to alter or in any way change the size or con- 

 formation of his skull. The same thing is true with regard to the length 

 of bones in the human body, and this had afforded the key to the sys- 

 tem of anthropometry adopted by M. Bertillon, as he has chosen for 

 his identification those portions of the body over which the individual 

 has no control, and in which it is impossible for him to make any 

 change in their size or length. The length of the head thus taken is a 

 measurement at once accurate, unchangeable, and beyond the control 

 of the individual or the possibility of deception. 



Maximum breadth of head. — This is measured from one parietal bone 

 to the other in the same manner as the length of the head is measured. 



Maximum lemjth of arms .1 extended. — This is a measurement which is 

 popularly supposed to be always equal to the height, but in reality it 

 may vary from 5 to 20 centimetres. It assists therefore in classifying 

 even after the height. 



Length of middle finger of left hand. — This is the best of our indications, 

 for it can be measured to a millimetre, provided care is taken that the 

 finger is bent at an exact right angle with the back of the hand ; there 

 can be no cheating with this and it undergoes no alteration from adult 

 to old age. Notice must, however, be taken of any unusual length of 

 nail in the person being measured. 



Maximum length of left foot. — In taking this measurement the subject 

 must, of course, be barefoot, and in order to avoid any chance of cheat- 

 ing the subject should stand on the left foot only, with the left knee 

 bent. This is not quite so good a measurement for our purposes as that 

 of the middle finger, and can only be measured to within 2 millimetres. 



Color of the eyes. — A special table has been framed for the color of the 

 eyes, which gives seven categories. These are based on the intensity 

 of the pigmentation of the iris. Firstly, we note the exact shade of 

 the pigment when it exists, and secondly, the approximate shade of 

 the deep stratum of the periphery of the iris. 



Hence the seven divisions : 



(1) Iris azure blue and slary blue with aureole concentric pupillary 

 aureole more or less pale but destitute of yellowish pigment. 



(2) Iris inclining more or less to blue or slate color, but with a light 

 yellowish aureole. 



(3) Same shade but with a further aureole, ai)proachiug orange. 



