EUGNATHIDJE. 
347 
greater than the depth of the bone at their insertion ; all the teeth, 
both upper and lower, very slender at the apex and often incurved. 
Symphysial end of the only known dentary bone considerably 
curved downwards. 
Form. Sf Log. Portlandian : Isle of Portland. Kimmeridgian : 
Dorsetshire. 
P. 6035. Type specimen, shown of one-half the natural size in 
PI. VII. fig. 4; Portland Stone, Isle of Portland. Both 
bone and teeth are much fractured, but the general form 
of the maxilla is distinct except at its hinder extremity. 
The very slender small teeth are indicated posteriorly, 
and the attenuated incurved apex is also shown on the 
principal teeth, some of which are fractured to expose the 
inner cavity. Presented by George Clifton, Esq., 1890. 
P. 6034 a. Middle portion of a similar maxilla, with teeth showing 
the smooth solid apex ; Portland Stone, Isle of Portland. 
Presented by George Clifton , Esq., 1890. 
42381. Anterior portion of left maxilla and other fragments ; 
Portland Stone, Isle of Portland. Purchased, 1870. 
40719. Bight maxilla, inner aspect, wanting the hinder portion 
but with well-preserved remains of teeth showing their 
characteristic form : Ivimmeridge Clay, Dorsetshire. 
Purchased, 1867. 
P. 6034. Imperfect right dentary, shown from the outer aspect of 
one-half the natural size in PI. VII. fig. 5, remarkable 
for the crowding of the anterior teeth and the downward 
curvature of the bone towards the symphysis (s.); Port¬ 
land Stone, Isle of Portland. 
Presented by George Clifton , Esq., 1890. 
Caturus (Ditaxiodus) impar (Owen). 
1866. Ditaxiodus impar, B. Owen, Geol. Mag. vol. iii. p. 107, pis. iv. & v. 
Type. Jaws ; British Museum. 
The type species of the so-called genus Ditaxiodus, known only 
by the jaws, which indicate a fish perhaps about 1 metre in length. 
Maxilla thick but less deepened than in any of the preceding 
species, much arched throughout the greater part of its length, and 
the height of the middle teeth considerably exceeding the depth of 
the bone at their insertion. All the teeth, both upper and lower, 
