Geology and Paleontology. 447 
which are common to the two forms, which does not appear to be 
justified by the specimens; on the development of 4 to 6 dorsal 
spines, of spinous rays to each pectoral (“ pectorales radiis duobus 
spinosis”), and of 1 to 3 spines to each ventral (“ ventrales radiis 
1—3 spinosis, retro-flexis’”’). Such features as the last two are so 
incompatible with the structure of living Scleroderms that the sus- 
picion is unavoidable that their ascription to the extinct forms is 
due to some error of observation or interpretation. The principal 
feature described and corroborated by the illustrations is the num- 
ber of dorsal spines. The arrangement of the spines is neverthe- 
less very different in the two species. 
thidids ; the family name in such case would of course be Proto- 
balistide. 
of the back; the first spine is very strong and the others very 
short; the soft dorsal is elongated, and the anal is oblong; the cau- 
dal peduncle is 
well as the structural characteristics (so far as known) of the 
be 
to that family, and that it is related to the genera Triacanthodes 
and Hollardia, with which it agrees in the convex caudal fin, 
oie the elongated ventral spines. (“Le ventrali sono constituite 
Delle pettorali non si scorge sull ’esemplare alcuna traccia e delle 
TAitralo si vede soltanto un Solá raggio pom se lungo tre centimetri 
piegato all ’indientro lungo il ventre (p. 4). 
