368 MR. R. I. POCOCK ON THE 



did not distinguish between the orifice of the sac and that of 

 the rectum which lies within it. That this would be a difficult, 

 task in a living animal is quite credible. Indeed, in such a form 

 as M. auropunctatus, it is easy at first sight to believe that the 

 sac itself is merely an enlarged anus, that its thickened rim is- 

 the anal sphincter, and that the small rectal orifice within the 

 sac arises from constiiction of the gut just within the anus ; 

 and this view would be sti"engthened by the discovery of the 

 apertures of the anal glands well outside the inner orifice and not 

 within it, where, by the analogy of other carnivores, they should 

 be situated if the orifice in question were the anus. There are 

 reasons which make me judge- that conclusion to be wrong. 

 In the first place, the external orifice of the sac is not shut by 

 the constriction of a circular sphincter muscle as the anus is ; 

 but when closed it forms a transverse, sometimes crescentically 

 upcurled, rima by the juxtaposition of its upper and lower 

 margins (text-figs. 9, C, and 10, A). In the second place, the 

 walls of the sac, sometimes at all events, show short hairs 

 projecting from the cutaneous follicles, suggesting its origin from 

 the involution of hairy circumanal integument. Finally, the 

 inner orifice itself is provided with a sphincter muscle. The 

 external position of the a,pertures of the anal glands, although 

 unusual, is not without parallel in the Carnivora, as is attested 

 by the condition seen in Hycena and Proteles. 



In the Mongooses the position of these apertures varies. 

 Usually they are set one on each side of the anus, and tolerably 

 close to it (Mttngos mungo) or removed to some distance from it 

 (Ariela, Suricata). In other cases they are placed somewhat 

 (^Ichneumia) or considerably (^Cynictis) higher up in the anal 

 sac (text-fig. 9, D, E). 



The secretion of these glands is always liquid and foul-smelling 

 and often copious. But, in addition, the free wall of the sac is 

 provided with well-developed cutaneous glands of the ordinary 

 kind, sometimes fairly miiformly distributed (Atilax), sometimes 

 especially active and large in a half circle above the anus 

 (Mtongos), sometimes located in definite paired areas of the sac. 



Three of the genera, however, call for more detailed notice, 

 since the published descriptions of their glands do not agree in 

 all particulars with my observations. 



When claiming for the first time the close and congeneric- 

 affiliation between Crosscirclais ohscurus and Ariela fasciata^ 

 Thomas added the following paragraph (P. Z. S. 1882, p. 86, 

 note) : — " Since the above was written, Prof. Mivart has pointed 

 out to me that the researches of Chatin into the structure of the 

 anal glands of the Carnivora (Ann. Sci. Nat. (5) xix. p. 89, 1874) 

 fully confirm the opinion here expressed as to the generic re- 

 la.tionship of the Striped Mongoose ( C.fasciatfis) with C. obscicncs."' 

 Chatin does not, however, mention C. ohscurits in the paper 

 referred to ; and that Thomas was misled by Mivart is clearly 

 shown by the remarks of the latter on the subject in question 



