174 R- J- Anderson, 



A rapidly enlarging ossifie district may mean the curtailing- of 

 some other ossifie district, and a falling short absolutely or relatively 

 may lead to the deposit of wormian bones ultimately or the growth 

 of an adjacent bone or the revival of some ossicle which has long 

 since disappeared. 



De Blain ville figures the fronto-premaxillary suture in Ursus 

 Malayanus as in front of the orbit. If De Blainville's skull was 

 Helarctos we have there a variety. In the specimen described here 

 the suture is 4 mm further back than the anterior margin of the orbit. 

 It is different in Ursus Americanus and polaris, for in the former 

 the suture is 6 mm and in the latter 10 mm in front of the anterior 

 margin of the orbit. 



The figure of Ursus ornatus given by De Blainville shows the 

 nasals very short, the frontals reach farther forward owing to the 

 shortened nasals. The Premaxillae are broader at the upper end than 

 is usual. Herpestes, Procyon and Paradoxurus are all figured, but many 

 of his other figures are old skulls. The groove referred to above is 

 in U. Malayanus, 8 mm in front and 4 mm behind as measured from 

 edge to edge. 



The follow summary may be given for the species examined or 

 referred to! — 



1. Whilst with rare exceptions the Premaxillas articulate with the 

 frontals in the ursidae the line of suture varies in position. 



2. The articulation varies in the length and character. 



3. The front nasal articulation varies in position with reference to 

 the orbit. It is in front in Malayanus of the summit of the 

 fronto-maxiUary suture, on the same level in Ursus x\mericanus, 

 and labiatus and much further back in Ursus (Thalassarctos) 

 maritimus. 



4. In some of the Canidae the P. Maxillae appi'oach the frontals 

 but in others a considerable interval is placed between these bones. 



5. The allies of the bears resemble the latter in tlie approximation 

 or actual Contact of the frontal and maxillae. Tlic Condition 

 in seals is remotely different. 



