46 Memoirs of the Indian Museum. [Voiv. I, 



13. Breadth of upper molar series = Up. Mol. B. — I used callipers for this, read- 

 ing them off on a steel scale graduated to half millimetres. It is a very unsatisfactory 

 method as the margin of error is so large compared to the actual measurement. To 

 get accurate results one would require a fine, automatic outside gauge, reading up to, 

 say, one-tenth of a millimetre. 



14. I^ower jaw, condyle to incisor tip = Lower Jaw C. to I. from the condyle 

 to the tip of the incisor. Coronoid to Angle = C. to A. From the angle to the most 

 elevated point of the coronoid process. 



In these measurements I have followed Thomas as best I knew how, except that 

 for his length and breadth of the interparietal I have substituted the maximum cranial 

 breadth. The interparietal is so variable in shape that its measurements are not 

 of great importance. 



Miller, in addition to basilar length, gives also (i) basal length, but without defining 

 the phrase ; and also adds the following : (2) least width of palate between anterior 

 molars ; (3) combined breadth of nasals ; (4) mastoid breadth of cranium ; (5) 

 occipital depth at front of basioccipital ; (6) fronto-palatal depth at posterior 

 extremity of nasals ; (7) least depth of rostrum immediately behind incisors ; a 

 total of 21 measurements. 



Whether these measurements are worth the time and trouble they take is open 

 to grave question ; to be of any use they must all be reduced to percentages, and if 

 the idea be to give a metric picture of a skull on the lines of anthropometry, then 

 numerous as they are, they are still too few. For diameters must be placed definitely by 

 means of longitudinal measurements. As showing the fallacy of cranial indices let 

 me quote an unpublished example from my own experience. I measured two 

 friends, A, a fair, short, bullet-headed Saxon, B, a dark, narrow-headed, Celt to find 

 to my astonishment that they had practically the same cephalic index ll^ef^; and 5^3^; 

 75-3 and 75 respective indices. To indicate in figures the marked difference between the 

 skulls I found it necessary to compare the maximum anterior cephalic diameter taken 

 in vertical line above the middle of a line joining the orbit and the meatus ; these 

 were respectively 15 cm. and 13-5 cm. The fact is that three good illustrations of 

 the different aspects of the skull are worth three pages of description. 



Wherever possible a label with the fresh measurements should be attached 

 to every rat before placing it in spirit, if it is to be sent for examination. Rats 

 putrefy in India with extreme rapidity, so that they should be placed in spirit 

 immediately they are killed, and the precaution should be taken of opening the 

 abdomen or putrefaction may proceed even in the spirit. Sex and locality, elevation 

 if a hill rat, and date of capture, should all be recorded on the label, which should be 

 written in pencil not in ink. FormaHn should be avoided, as in India at least it is 

 an utterly unreliable preservative for mammals. As the result of receiving from 

 Darjeeling consignments that should have been of rats preserved in formalin, but 

 which were more like tins of formalin rat-soup, I carried out a series of experiments. 

 These showed that even for small rats 8 per cent, was required, and that for large 

 thick-skinned rats even 12 per cent, was insufficient to prevent putrefaction. 



