-^ So/i/Iicni C^ross. 



lliu nornml lorinulu Un- --tlicr Seals. In skull N... 4 the Inniiula for 

 the ohei'k-toHh is pni. ;.ii.l m. '.' ^ .'. In tliu case of the iipper juw 



the lesser size ("f the hist two teeth .suji,i,'ests that, as in skull No. TOO 

 (• Brhjira '), they are the representatives of the typical fifth grinder. 

 <»n the ri^lit si(h' an«l on the left side each is provided with double 

 nwts. The rmiaining teeth resemble those of No. 43.11.25.4, 

 Unnj; all. with one exception, more or less provided with double 

 nniU The sin<,'le exception is the first, which, as in every other 

 known instance, is single rooted. 



In No. :*. the formula is again p.m. and m. , where, if we 



5X5 



still apply Mr. P>ateson's hypothesis, it appears to be the last tooth 



whirh has undergone redu])lication. The supposed " daughter " teeth ^ 



an', however, remarkable in two ways. In the first place they are 



not small teeth as is the case in the two instances already described 



(Xos. 7<»» and 4). On the contrary, one of them (the anterior one), 



is, like all the teeth of this particular specimen, uncommonly robust, 



and probably larger than any single fifth tooth of any known skull 



of this species. The posterior one is smaller than its comrade ; but 



still not small when measured by the standard of the " daughter " 



toeth of other specimens. Secondly, these teeth are unique, amongst 



four similar instances, in being l)oth single-rooted. Opposite to these 



teeth in the lower jaw we have a tooth which is again unique of its 



kind, being the only absolutely single rooted m. — in the whole 



series. It looks as if the development of the teeth of one jaw had 



had some influence on those of the other. All the cheek-teeth of 



the left upper side are single-rooted, the roots of the third, fourth, 



un«l fifth being Itroad and grooved. Those of the right upper side, 



with the excej)tion of the first, second, and last, are double-rooted. 



In the low.M- jaw all are double-rooted except the first and last. Of 



1 2 



thrxc i..m. iind " are crowded and slightly overlap each other. 



Tlnr whoh" head is remarkable for the great size of the teeth. These 

 are an remarkable for their unusually large, as are those of No. 897, 

 for their unusually small size. 



No. 2 pre.sents us with a fourth instance where the formula is 



JUjain jun. and m. -L^ _'. In this case each supposed " daughter " 

 trwiih is fidly pn.vid.Ml with doulde roots, those of lit.' List forming 



I Lurrnw (),;-- I, .,-,11 tVniii Mr. H.-itcson. 



