208 



NORTH AMERICAN MUSTELID^. 



specimens are not onl^- 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.' 



" Measurements of twenty-nine slculls of Mephitis mephitica. 



Anatomy and i^hysiology of the anal glands and properties of 



the secretion. 



The almost insuperable repugnance which the Skunk natur- 

 ally excites has always been an obstacle to the investigation of 

 its peculiar defensive organs. Until quite recently, when M. 

 Chatin minutely examined the anal glands of Conepatus mapu- 

 rito, no adequate account of any species had been rendered, 

 though these parts in M. mephitioa had long since been briefly 

 noticed. The first, and for a long time the only accurate, record, 

 was that given by Dr. Jeffries Wyman in the first volume of the 

 Boston Natural History Society's Proceedings (1844, p. 110). 

 This indicated, though briefly, the general structure of the 

 parts which obtains throughout the family, as far as known. 



