312 Proceedings^ of the Royal Irish Academy. 



as I tliink, most remarkably, removed "by the accidental trapping of a 

 Badger. In tMs animal, as is -well known, altkougli tke case is not 

 nearly so conspicuous as are many others, the deepest tints occur on 

 the under side. In the particular specimen (a male) the upper surface 

 of the body, with the whole tail, and the inguinal region, was con- 

 trasted by its light colouration with the remaining portions of the 

 under side. On examining the carcase, I found that the lightest ex- 

 ternal parts, viz., the ramp, tail, and inguinal region, lay over the 

 thickest accumulation of fat. A thinner layer of fat extended over 

 the whole back, whereas the upper belly and breast were almost free 

 from fat. Thus external colouration was here directly con-elated with 

 the distribution of the pamiictdus adiposKs. In view of this fact, it 

 seems probable that certain of the colour-differences which help to 

 distinguish some of the foreign species of Eadgers from our own are 

 due to further developments of the pannicidus adij^osus, for they 

 frequently follow the line which would be taken by winter whitening 

 on a Hare or that in which fat is deposited on an ox. That is to 

 say, when a Badger differs from our own species in regard to the 

 lightness of its upper surface, we may almost predict that the lightest 

 part will be the rump, while in another species the white will have 

 undergone further extension up the back. Thus a series of skins of 

 tlie various species of Badgers may be almost made to match (in 

 regard to the whiteness of the upper side), one consisting of the skins 

 of Hares in process of whitening. 



The second difficulty was upset in a most unexpected manner when 

 I came to examine the animal's head. There I found that the thi'ee 

 white bands lay over three regions of the skull where no flesh intervenes 

 between the bone and the skin : the three white external bands were, 

 in fact, clearly marked out by three similar cranial bands of ligament 

 and bone. Here, then, was the most unexpected fact that not only 

 may deficiency of pigment be associated with the presence of under- 

 lying subcutaneous fat, but also with that of bone or ligament. So 

 that we may almost lay down the law that there is a tendency to 

 jjigmentaiy abeiTations at those parts of the body where nutrition of 

 the skin is interfered with by contact with underlying fat, bone, or 

 ligament, or better, that adjoining regions of uneven nutiition tend to 

 originate unevenness of external pigmentation — a result which ilr. 

 Alfred Tylor missed by very little in 1886.^ 



It is obvious that this conclusion, if further borne out, may exercise 



1 " Colouration in Animals and Plants ; " London, 1886. 



