506 



DB. .1. JIJ.EIE OX THE ANATOMY OF THE SEA-LION. 



adjoining minute accessory tiny open fork, situate behind but to the inside of the ovale, 

 and immediately in front of the periotic. The latter nodular bone dominantly projects, 

 a concavity of the cerebellum at the flocculus resting thereon. Anteriorly the aquse- 

 ductus Fallopii is barely visible in this view ; neither is the meatus auditorius internus, 

 which looks towards the median line ; and the aquaeductns vestibuli similarly occupies 

 a recess on the posterior face. Below the last is the carotid canal, behind the large 

 jugular perforation. An anterior condyloid foramen pierces the corner betwixt basi- 

 and exoccipitals, running nearly vertically towards the jugular groove. 



For a description of the longitudinal vertical section of the aged skull, viz. that in 

 PL LXXVII. fig. 22, I refer to Prof Owen's notice in the Cat. Coll. Surg., specimen 

 No. -3971. It is sufficient for my purpose to call attention to the great occipital crest, 

 thickness of frontal, position of ethmoid and turbinals, maxillo-palatine cleft, and 

 osseous tentorium, as all more fully pronounced in character than what obtains in 

 younger skulls which, nevertheless, in other general respects agree. 



f. Sexual differences. — In a previous communication to this Society, I directed attention 

 to certain visual distinctions extant between the male and female skulls of Otaria julata, 

 and gave figures of the same, hereunder reproduced. I was not then aware that Owen 

 had commented on the same fact, and therefore now append his remarks in a footnote '. 



ris. 1. 



Palatal views of adult male (tig. 1) aud female (fig. 2)- skulls of Otaria jubaia. To scale j nat. size. 

 Prom P. Z. S. 1869, p. 103. 



' " It differs from that of the male iu its inferior size, but agrees with it in all essential or modifiable cha- 

 racters. The more feeble bite and smaller temporal muscles have not required the elevation of the temporal 



