474 MR. R. I. POCOCK ON THE 



Mustela. Flower's statement about the absence of the alisphenoid 

 canal may stand with the qualification that the canal may be 

 retained as an abnormality. 



In 1885, Mivart (Proc. Zool. Soc. pp. 363-389) supplemented 

 Flower's observations with a few additional facts and included 

 Conejjatii/S, Pmcilogale, and Lyncodon in the list of genera. 



Since that date it does not appear that the facts have been 

 re examined. The observations contained in the following pages, 

 based mainly on specimens that have died in the Society's 

 Gardens, may, therefore, be interesting and useful. 



The Foramina in the Base of the Skull. 



The Alisphenoid Canal. — This tube, as is well known, is 

 typically absenb in the Mustelid^e. But in one example of 

 Lutra Intra, I find the remnants of it on the left side of the skull 

 although the right side is normal. A little distance in front of 

 theforameji ovale and higher up there is a small orifice through 

 which a bristle can be passed so as to appear in the apertui'e 

 common to the foramen lacerum anticum and the foramen 

 rotundum. The passage is no doubt the homologue of the 

 alisphenoid canal in the Canidfe, Ursida3, Ailurus, Mungotidse, etc. 

 Except as an item of evidence supporting the view that the canal 

 in question is a primitive Carnivore feature, the discovery of it 

 in a skull of Lutra is of no great moment. As I have elsewhere 

 pointed out, it may be present or absent in the Hysenida? (Proc. 

 Zool. Soc. 1916, p. 444, fig. 2). 



The Posterior palatine foramina. — The normal position of 

 these is approximately opposite the inner lobe of the upper 

 carnassial tooth {pm.*) on the maxillo-palatine suture, along 

 which they move to a certain extent backwards or forwards. 

 They hold this position in Maries, Charronia, Giolo, Tayra, 

 Mellivora, Meles, Arctonyx, Mydaus, and Helictis. In Taxidea 

 they may be as far back even as the anterior edge of the molar. 

 In Lyncodon, Grison, Ictonyx, Poecilictis, Lutra, Poecilogale, 

 Vormela, and Mustela, with its related generic and subgeneric 

 forms, Gale, PiUorius, Lutreola, they are on the maxilla 

 approximately opposite poji. 3 and removed from the maxillo- 

 palatine sutui'e. In Mephitis, Spilogale, and Conejjatus they may 

 be even nearer still to the anterior palatine foramina, opposite 

 pvi. 2. 



It may be noticed that in all the genera with long jaws like 

 Meles, Arctonyx, Mydaus, Helictis, and Martes they are set back 

 on the suture, whereas in some genera with short jaws and often 

 reduced dentition, like Mustela, Vormela, Grison, and I^utra, 

 they are set forwards, wholly on the maxilla. Nevertheless this 

 position is not always correlated with the length of the jaws and 

 teeth, since they occupy the backward position in Mellivora and 

 Taxidea. 



Their variation in position within the Mustelidse is interesting 

 in view of their constanc}'' in position in other families of 



