360 
A CXI X 0 PIER T G11. 
Lophiostomus afHnis, A. S. Woodward. 
1895. Lophiostomus crffinis, A. S. Woodward, Geol. Mao-. ("41 vol. ii. 
p. 210, pi. viii. fig. 6. 
Type. Hinder portion of cranial roof; British Museum. 
A species as large as L. dixoni, known only by the hinder portion 
of the skull, which is somewhat more finely ornamented than in the 
type species. Frontal prominences slight, not forming a slender 
eminence. 
Form, Loc. Cenomanian (Cambridge Greensand): Cambridge. 
P. 7233. Type specimen described and figured loc. cii. Jesson Coll. 
Family AMIIDkE. 
Trunk elongate or elongate-fusiform, more or less laterally 
compressed. Cranial and facial bones moderately robust, externally 
enamelled, and opercular apparatus complete ; mandibular suspen- 
sorium nearly vertical or inclined backwards, and gape of mouth 
wide ; snout not produced ; premaxillse separate and in contact 
mesially ; marginal teeth mostl}’ stout and conical, inner teeth com¬ 
paratively small or even minute. Notochord persistent or more or 
less replaced by vertebrae, which remain as disconnected pleuro- 
central and hypocentral discs in part of the caudal region. Fin-rays 
robust, the majority well-spaced, articulated and divided distally; 
fulcra almost or completely wanting ; dorsal and anal fins variable 
in length. Scales thin and deeply imbricating, more or less rounded 
in their exposed portion. 
The characters of the genus Liodesmus , mentioned below, render it 
difficult to compile a satisfactory diagnosis of this family, which 
must be regarded as a specialised branch of the Eugnathidae. 
The principal descriptions of the osteology of the type genus, the 
existing Amia of North American lakes and rivers, are the 
following :— 
H. Franque, “ Afferuntur nonnulla ad Amiam calvam accuratius 
cognoscendam ” (Inaugural Dissertation : Berlin, 1847). 
T. W. Bridge, “ The Cranial Osteology of Amia calva ” (Journ. 
Anatomy & Physiol, vol. xi. 1877, pp. 605-622, pi. xxiii.). 
M. Sagemehl, “Das Cranium von Amia calva” (Morphol. Jahrb. 
vol. ix. 1884, pp. 177-228, pi. x.). 
R. W. Shufeldt, “ The Osteology of Amia calva ” (Ann. Rep. U.S. 
Commiss. Fisheries, 1883 [1885], pp. 747-878, pis. i.-x.). 
