242 EUMETOPIAS STELLERI STELLER's SEA LION. 



the hyoid bone is reduced almost to a bony filament. The length 

 of the hyoid bone in the present species is 270 mm. ; of the trans- 

 verse segment, 65 mm. ; circumference of the transverse segment, 

 45 mm. 5 of this segment at the thickest part, 95 mm. 



The os penis is 170 mm. long, slightly arched, somewhat flat- 

 tened above, especially posteriorly, sharply convex below, and 

 abruptly expanded and squarely truncate at the end. Its cir- 

 cumference at the base is 72 mm. ; just behind the terminal ex- 

 pansion, 32 mm. ; of the terminal expansion itself, 65 mm . 

 Measurements of the Skeleton. 



No. 2920, 

 rf.lOy 

 old. 



No. 2921, 



cf,15y'rs 



old. 



Whole length of skeleton (including skull) 2,750 



Length of skull 374 



Length of cervical vertebrae 500 



Length of dorsal vertebrae 1,050 



Length of lumbar vertebrae 340 



Length of caudal vertebrae 440 



Length of first rib 260 



Length of firstrib, osseous portion 130 



Length of firstrib, cartilaginous portion 130 



Length of second rib 345 



Length of second rib, osseous portion 175 



Length of second rib, cartilaginous portion '- 170 



Length of third rib 410 



Length of third rib, osseous portion 230 



Length of third rib, cartilaginous portion 180 



Length of fourth rib 470 



Length of fourth rib, osseous portion 280 



Length of fourth rib, cartilaginous portion 190 



Length of fifth rib . 535 



Length of fifth rib, osseous portion 320 



Length of fifth rib, cartilaginous portion 215 



Length of sixth rib , 580 



Length of sixth rib, osseous portion 360 



Length of sixthrib, cartilaginous portion 220 



Length of seventh rib 640 



Length of seventh rib, osseous portion 400 



Length of seventh rib, cartilaginous portion 240 



Length of eighthrib 670 



Length of eighthrib, osseous portion 420 



Length of eighthrib, cartilaginous portion 250 



Length of ninth rib 710 



Length of ninth rib, osseous portion 420 



Length of ninth rib, cartilaginous portion 290 



Length of tenth rib 750 



Length of tenth rib, osseous portion 420 



Length of tenth rib, cartilaginous portion 330 



Length of eleventh rib, osseous portion only 430 



