/jCa*£> i 
/«^L'- LAt- r$A . ^ ojaf . IAU^ %j 2<rf 
ASTEROLEPID^]. 203 
/f ' e LV^ 
Family ASTEROLEPIDiE. 
Exoskeleton robust, ornamented with tuberculations of ganoine : 
dorsal and ventral shields of trunk firmly united by the lateral 
plates. Orbits very closely approximated, and the interorbital 
piece loose. A pair of paddle-like appendages, completely encased 
in bony plates, articulated by a complex joint with the anterior 
ventro-lateral plates of the trunk ; median fins not continuous. 
As pointed out especially by Traquair, the dermal plates in the 
genera of this family are arranged upon one definite plan, and the 
most satisfactorily known genus, Pterichihys , may be taken as a 
typical example. This is described in detail under its generic 
heading (p. 208), and notes on the homologous parts of Bothriolepis 
are added later (p. 224). ik \J0XI, \j -n . ^ ^ 
. Ua-Cov rs<z WoteW Vi\ir*«4 C»35 
Synopsis of Genera. . 
I. Pectoral appendages shorter than the body- 
armour. 
Anterior median dorsal plate overlapping the 
dorso-laterals. Asterolepis (p. 203). 
Anterior median dorsal plate overlapping 
the anterior dorso-lateral, overlapped 
by the posterior dorso-lateral. Pterichthys (p. 208). 
Anterior median dorsal plate in front over¬ 
lapping and behind overlapped by the 
anterior dorso-lateral and the posterior 
dorso-lateral . Microbrachium (p. 223). 
II. Pectoral appendages longer than the body- 
armour. 
Anterior median dorsal plate overlapping the 
anterior dorso-lateral, overlapped by the 
posterior dorso-lateral . Bothriolepis (p. 223). 
A XJ (JUA, 
S 
Genus ASTEROLEPIS, Eichwald^ / /feiA 
[■Bull. Sci. St.-Petersbourg, vol. vii. 1840, p. 79 {Astrolejois).'] 3 ? t 4 .- 
Syn. Chelonichthys, L. Agassiz, Poiss. Foss. vol. i. 1844, p. xxxiii 
(name only). 
Odontacanthus , L. Agassiz, Poiss. Foss. V. G. It, 184o, pp. Ill, 
114. 
(?) ActinoJepis , L. Agassiz, ibid. p. 141. 
(?) barcodes, L. Agassiz, ibid. pp. Ill, 115. 
Head and trunk broad, not much elevated, the scutes ornamented 
