176 Reviews — Prof. Fritsch—Fauna of Gas-coal. 
of the twelve plates contained in the present ‘“‘ Heft,” while in the 
remainder a commencement is made with the description of these 
«‘Teleostomi,” which we have been accustomed to call ‘“‘ Ganoidei.” 
Only one family of Acanthodei is represented in the newer palzo- 
zoic rocks, that of the Acanthodidae, having only one dorsal spine, 
and of this family the genera and species occurring in the Permian 
of Bohemia are first treated descriptively, a separate chapter being 
reserved for general considerations. Three genera come under con- 
sideration, namely Traquairia, Protacanthodes and Acanthodes, of 
which the two former are new. 
Traquairia pygmaea is the name given by Dr. Fritsch to a small 
Acanthodian fish whose salient peculiarities are—the total absence 
of ventral fins and the tooth-like acumination of the posterior angles 
of the scales,—the dorsal spine is, as in Acanthodes, behind the anal. 
Numerous examples of the one species of the genus have occurred at 
Nyran, and a few also at 'Tremosna. 
In Protacanthodes the scales have also a spine or tothe like pro- 
jection which, however, passes off from their hinder margin; the 
ventrals are described as very small, while behind them a long 
narrow median dermal fold passes to nearly as far as the anal spine, 
which as in Traquairia and Acanthodes is placed in front of the 
dorsal. It is much to be regretted that only one single example of 
the one species, P. pinnatus, Fr., has occurred. Dr. Fritsch seems 
himself a little doubtful about the minute ventrals, and I cannot 
altogether rid myself of the notion, that what he interprets as a 
median fold may possibly be one of a pair of ventral fins, fringe- 
like as they are in Acanthodes proper. Of the last mentioned genus 
three species are noticed, of which A. punctatus is founded upon 
spines occurring at Kounova, while A. Bronni, Ag., and A. gracilis 
(Beyrich) are retained as distinct species. 
As regards the general structure and morphology of the group, 
Prof. Fritsch exercises a wise caution in not committing himself to 
such wonderfully detailed results as those announced by Reis in a 
paper published three years ago.’ He places the Acanthodei among 
the Elasmobranchii as is now done by most authors, and among the 
evidences of this affinity he adduces the tooth-like projection on 
the posterior aspect of the scale, in Traquairia and Protacanthodes, 
which he compares with those of Centrina. The resemblance in 
shape is interesting, but I cannot follow the author when he says: 
“Hs zeigt sich dass die iilteren Formen der Acanthodiden diese 
bezahnten Schuppen trugen und ihre jiingeren Vetreter Acanthodes 
diesen Zahn verloren und blos den viereckigen Theil ohne jeden 
Vorsprung behalten haben.” I certainly cannot regard either 
Traquairia or Protacanthodes as specially archaic in structure, and 
I certainly know of no Devonian or Carboniferous Acanthodian which 
is possessed of similar “ bezahnte Schuppen.” 
As regards the skeleton he finds that the cartilage calcifications 
are as in the Xenacanthide formed by polygonal plates. No teeth 
1 Geognostische Jahreskefte der kénigl. baier. Oberbergamtes 1890. 
