52 
CHIMJSROIDEI. 
Chimseropsis paradoxa, Zittel. 
1843. “ Knochen,” H. von Meyer, in Munster’s Beitr. Petrefakt. i. p. 96, 
pi. viii. fig. 1. 
>.887. Chimceropsisparadoxa, K. A. von Zittel, Handb. Palosont. vol. iii. 
p. 114, woodc. fig. 126. 
1887. Chimceropsis paradoxa, J. Biess, Palaeontogr. vol. xxxiv. p. 21, 
pi. ii. figs. 9-11, pi. iii. figs. 1-10. 
Type. Imperfect skeleton; Palaeontological Museum, Munich. 
The type species, attaining a length of not less than one metre ; 
dorsal spine in such a specimen O’15 in length. Two closely 
apposed, angulated dermal plates on either side ot the back of the 
head. Dorsal fin-spine rapidly tapering, gently arched, and all the 
anterior denticles pointing upwards. Mandibular tooth robust in 
appearance, with prominent beak and gently excavated, scarcely 
undulating oral margin; presymphysial tooth sharply rounded in 
front. Vomerine tooth about one and a half times as long as its 
maximum width behind; the maxillary tooth much narrower. 
Form. Sf Log. Lower Kimmeridgian (Lithographic Stone): Bavaria. 
Not represented in the Collection. 
To Chimceropsis also must doubtless be assigned the first of the 
dorsal fin-spines described as follows :— 
Myricicanthus franconicus, G. von Munster, Beitr. Petrefakt. iii. 
(1840), p. 127, ph hi. fig. 8.—Upper Jurassic; Babenstein, 
Bavaria. 
Myriacanthus vesiculosus, G. von Miinster, ibid. v. (1842), p. Ill, 
pi. vi. fig. 3.—Corallian; Lindnerberg, Hanover. [?Frag- 
ment of Aster acanthus.] 
A spine from the Lower Carboniferous of Bussia, certainly not of 
the Myriacanthidse, is named Myriacanthus semigranulatus , H. Bo- 
manowsky, Bull. Soc. Imp. Nat. Moscou, 1864, pt. ii. p. 167, ph iv. 
fig. 34. 
Family CHIMLERIDLE. 
Body elongated; anterior dorsal fin above the pectorals, provided 
with a long, straight, robust spine. Teeth forming two pairs of 
robust dental plates in the upper jaw, both pairs thickened and 
closely apposed in the longitudinal mesial line of the mouth ; lower 
dentition consisting of a single pair of large, beak-shaped plates, 
meeting at the symphysis ; most of the plates with several tritoral 
areas. Dermal plates absent. Males with a prehensile spine upon 
the snout. 
