54 Southern Cross. 



the nuriiial foniiula fur other Seals. In sknll No. 4 tlie Ibnuula for 



the cheek-teeth is p.m. and m. _ ^. In the case of tlie upper jaw 

 ^ J:) X 5 



the lesser size of the last two teeth suggests that, as in skull No. 700 



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



On the right side and on the left side each is provided with double 



roots. The remaining teeth resemble those of No. 43.11.25.4, 



being all, with one exception, more or less provided with double 



roots. The single exception is the first, which, as in every other 



known instance, is single rooted. 



In No. 3 the formula is again p.m. and m. _, where, if we 



still apply Mr. Bateson's hypothesis, it appears to be the last tooth 

 which has undergone reduplication. The supposed " daughter " teeth ^ 

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

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

 (Nos. 700 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 " 

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

 four similar instances, in being both single- rooted. Opposite to these 

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



kind, being the only aljsolutely 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, 



and fifth being broad and grooved. Those of the right upper side, 



with the exception of the first, second, and last, are double-rooted. 



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



1 2 



these p.m. — and — are crowded and slightly overlap each other. 



The whole head is remarkable for the great size of the teeth. These 

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

 for their unusually small size. 



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



again p.m. and m. i — ^. In this case each supposed " daughter " 



tooth is fully provided with double roots, tliose of the last forming 



' I liorrow this tenii IVoiii IMr. I'ateson. 



