333 



excelled iu size the three from California. The southern series represents 

 the so-called M. varians of Gray and Baird. 



The unsatisfactory character of the several species of North American 

 Skunks of the mephltica group, and the wide range of color-variation 

 among individuals from the same locality, I have previously had occa- 

 sion to notice,* and a re-examination of the subject confirms the con- 

 clusions then announced, which, I am happy to find, have recently 

 received the support of Dr. Coues, who has lately made a study of tliis 

 group.t As Dr. Coues has remarked, and as the subjoined measure- 

 ments show, few species of animals vary so much in size and in cranial 

 characters as the present, independently even of sex and age. Some 

 specimens are not only more than one-fourth larger than others, but 

 "there is a corresponding range of variation in contour. Compared 

 with an ordinary ratio of osteological variability," says Dr. Coues, " the 

 discrepancies are almost on a par with those exhibited by the coloration 

 of the animal when set over against the more constant markings of most 

 animals." In view of this great degree of variability, however, Dr. 

 Coues has ventured to describe a "new species" {M. frontata),\)ased 

 on a fossil skull from one of the bone-caves of Pennsylvania, as it seems 

 to me, unadvisedly. The specimen, though that of a very aged indi- 

 vidual, is scarcely larger (see subjoined table) than the average of speci- 

 mens from the Eastern States, its chief difference from the average 

 skull consisting in an abnormal tumidity of the frontal region, arising 

 evidently from disease. It is a feature by no means confined to the 

 I)resent example, but is merely an extreme enlargement of the sinuses 

 of the frontal region often seen in specimens of the existing animal, evi- 

 dently resulting from disease. In 'No. 917 (Albany, K Y.), No. 8099 (Fort 

 Cobb, Ind. T.), No. 1878 (Calcasieu Pass, La.), and No. 1620 (Indian ola, 

 Tex.), the same tendency is strongly marked, which, in some of these 

 specimens, had they attained equal age, must have resulted in a malfor- 

 mation nearly or quite as great as is seen in the fossil skull in question. 



In this connection, I may add that a pretty careful examination of the 

 fossil remains of Garnivora, collected by Professor Baird many years 

 since from the bone-caves of Pennsylvania (of which this fossil skull of 

 the Skunk forms a part), has failed to show any of them to be specifically 

 diflferent from the species now or recently living iu the same region. 

 Many of them are remains of individuals of large size, but not exceeding 

 the dimensions of specimens of the recent animal from the same or con- 

 tiguous regions. These remains include, among others, the following 

 species : — Lynx riifus, Urocyon virgmianus, Mustela jyennanti, Mustela 

 americana, Putorius vlson, Lutra canadensis, Ilephifis mephitka (other 

 specimens than the '•'■frontata " skull). Procyon lotor, Ursus americanus, 

 etc. 



*See Bull. Mus. Comp. Zool., vol. i, pp. 178-181, Oct., 18i3i), 

 tBull. U. S. Geol. aud Geog. Surv. of the TenitorLes, vol. i, No. 1, pp. 7-15, 1875 



