BELONORETYNCHIDiE. 
17 
are shown. There are no satisfactory indications either 
of ribs or fins; and only fragments of the dorsal series of 
ridge-scutes are preserved. Enniskillen Coll. 
P.965 d. Imperfect mandible, much ornamented, with part of the series 
of arches of the axial skeleton of the trunk. Egerton Coll. 
fcicL 
B^Mfcorhynciras brevirostris, sp. nov. 
[Plate II. fig. 2.] 
1858. Belonostomus acutus, F. A. Quenstedt (err ore ), Der Jura, p. 234, 
pi. xxix. fig. 8. 
1892. Saurorhynchus acutus , 0. M. Reis, Geogn. Jahresh. 1891, p. 145 
(in part), figs. 1-3. 
Type. Head ; British Museum. 
A species of moderate size, the head attaining a length of about 
0*11. Head from three and a half to four times as long as its maxi¬ 
mum depth ; distance between the orbit and occiput scarcely if at all 
exceeding the maximum depth of the mandible, and the angular 
bone of the latter with long, nearly vertical hinder border, sharply 
rounded off inferiorly; dentition powerful, the posterior laniaries 
widely spaced and especially robust; superficial ornament con¬ 
sisting of short rugae, the majority directed longitudinally, [Trunk 
unknown.] 
Form. ^ Loc. Lower Lias : Dorsetshire. Upper Lias : Wiirtem- 
berg and Yorkshire. 
(i.) Lower Lias, Lyme Begis. 
40726. Type specimen, being a cranium and mandible wanting the 
extremity of the snout and marked by an oblique line of 
fracture across the hinder portion. The fossil is shown 
of the natural size in PI. II. fig. 2, and exhibits the 
principal characters of the head from the right lateral aspect. 
Remains of the posterior extension of the cranial roof (r.) 
occur above the operculum (op.), which is very small and 
similar in shape to that of B. acutus. The orbit (o.), 
narial opening (?i), and dentition are also indicated; and 
the form of the hinder portion of the mandible is especially 
well shown. The very large articulo-angular bone exhibits 
the form of the posterior and postero-inferior margin so 
characteristic of the species ; and there are abraded 
remains of the series of short vertical sensory canals 
which mark its upper border. Pipchased , 1867. 
39866. Small head 0055 in length, the maximum depth contained 
about three times in the total length, and the mandible 
part in. 
c 
