DAVIS : HETEEOLEPIDOTUS. 
407 
of the examples constituting Egerton's genus Heterolepidotus,they are 
larger along the median line in proportion to the fish, than in either 
of the species from the lias described hy Sir P. Egerton (Memoirs of 
the Geological Survey Decade XIII., pi. 2 and 3,) and the scales of 
the ventral and abdominal regions, whilst they have the elongated 
form, do not appear to have been nearly so numerous or occupied so 
large an area as those of Heterolepidotus latus, Eg. The dorsal fin 
is further removed from the head than in the case of the species 
hitherto described, and its rays are longer and capable of wider 
expansion. The form of the fish occupies a position intermediate 
between the deep-bodied R. latus, and the elongated and graceful 
outline of R. sauroides Though considerably smaller than those 
species it has the characteristics of being mature. 
The specimen now described, constitutes the third species of 
this genus, all from the lias of Lyme Regis. Hitherto no example 
of the genus Lepidotus has been described from the Lyme Regis 
locaHty, whilst in the Yorkshire Lias it is more commonly met with 
than any other form and Heterolepidotus is unknown. I suggest 
the name H. minor, on account of its comparatively small size, be 
applied to this species. 
Formation and Locality : Lias, Lyme Regis. 
