1 886.] 



COLUMELLA OF ICHTHYOSAURUS. 



407 



long inferior border, decidedly marked off from a short posterior 

 border, but the precise nature of its original articulation is unfortu- 

 nately not apparent. The pterygoid seems to have slipped some- 

 what from its natural position. 



Fig. 1. 



Fig. 3. 



Fi-. 4. 



j,c- -^ 



Fig. 1. Right columella of Ichthyosaurus, ruueh criislied ; inner side view. 



[B..M., No. 2W0. 40 * .] 

 Fig. 2. Lower- portion of right columella of Ichthyosaurus ; outer side view : 



pt, pterygoid ; o, crushed bones in orbit. [B.M., No. R 44.] 

 Fig. 3. Lower portion of le.ft cohimella of Ichthyosaurus intermcdius ; inner 



side view. [B.M., No. 2000. 15.] 

 Fig. 4. Left columella of Hatteria punctata ; outer side view : pt, pterygoid ; 



^i(, quadrate. 



The fragmentary skull of Ichthyosaurus ^ figured by Hawkins in 

 his 'Book of the Great Sea-Dragons,' pi. 19. fig. 1, also e.xhibits 

 the lower two thirds of the left columella, and this is interesting as 



^ This specimen has been identified with /. intermedius, Conyb., by Sir 

 Richard Owen, and bears his MS. label. 



