450 ON SCLERORHYNCHUS ATAVUS. [Nov. 19, 
The broad median cartilage is distinct, very robust, displaying the 
numerous well-calcified tesserae; and on either side of this the 
narrow area is comparatively thin, though exhibiting small tesserae 
that are more suggestive of cartilage-calcifications than of shagreen- 
granules. ‘The anterior extremity of the type specimen (Catal. Foss. 
Fishes B, M. pt. i. pl. iii. fig. 1) shows a single pair of broad 
Rostrum of Selerorhynchus atavus. 
lateral cartilages occupying the entire width of the snout outside the 
median rostral cartilage; and it seems probable that a similar 
arrangement exists in the new specimen now exhibited. A few rostral 
teeth occur, of the form already described in the British Museum 
Catalogue. 
“A third head and rostrum of Sclerorhynchus has lately been 
detected, mingled with remains of Teleostean fishes, upon a small 
slab from Mt. Lebanon in the British Museum (no. 53663). Though 
very imperfectly preserved, this fossil confirms the observations 
made upon the previous specimens, and also makes known the form 
aud proportions of the teeth in the mouth. These teeth are remark- 
ably similar to those of a Lebanon fish of which the hinder portion 
