26 



PISCES 



CLASS I 



Bavaria, and K gracilis, Davis, by a smaller skeleton from the Upper Cretaceous 

 of Sahel Alma, Mount Lebanon. Detached teeth from 

 the Oxford Clay of England and Corallian of Würtem- 

 berg; from the Chalk of England (N. microdon, Ag.) 

 and the Cretaceous of New Zealand (N. dentatus, Sm. 

 Woodw.) ; and numerous species from Tertiary forma- 

 tions (e.g. N. primigenius, Ag., Fig. 45). 



Chlamydoselache, Garman. Teeth with broad, back- 

 wardly extended base, and the crown consisting of three 

 slender, curved, subconical cusps, which are separated 

 by a pair of rudimentary denticles. Wide distribution 



in existing deep sea. Isolated teeth in Pliocene of Tuscany (C. lawleyi, 



Davis). 



Sub-Order B. CYCLOSPONDYLI. Hasse. 



Vertehral centra in form of simple constrided cijlinders pierced hy the notochord. 

 Teeth numerous, triangulär, and acuminate, simple or with small lateral cusps. Eare 

 in the fossil state ; Upper Cretaceous to Recent. 



Fig. 45. 



Notklanns primigenins, Ag. 

 Lower tooth. Oligocene; 

 Weinheim, Hesse Darmstadt. 

 Natural size. 



Family 1. Spinacidae. Müller and Henle. Spiny dog-fishes. 



Body fusiform to trihedral, somewhat depressed. Mouth gently arched ; snout 

 obtuse. Gill clefts small, lateral ; spirades large, hehind the eye. Pedoral fins not 

 notched at their origin and not produced forwards ; the two dorsal fins offen armed 

 with a spine ; anal fin absenf. Upper Cretaceous to Recent. 



Centrophm'us, Müller and Henle (Fig. 46). Dorsal fin spines present. 

 Upper teeth erect, triangulär, or narrow lanceolate, with a single cusp ; lower 



teeth triangulär 

 and compressed, 

 with the apex 

 much turned aside. 

 Upper Cretaceous, 

 Sahel Alma, Mount 

 Lebanon (Spinax 



Fig. 4Ö. 



Vertebra (central double-cone) 

 of Cenfrophorus. Upper Cre- 

 taceous ; Maastricht (after 

 Hasse). . 



Fig. 47. 



Acanthi(ts radicaim, 

 Probst. Tooth, x 2. 

 Miocene (Molasse) ; 

 Baltringen, Würteni- 

 berg (after Probst.) 



Fig. 48. 



Scymnus triangulus, 

 Probst. Tooth, x 2. . -r»- i. i.\ 



Miocene (Molasse); pnmaeVUS, riCtet;. 



Baltringen (after T>f,f.f,j.f 



Probst.) xieceni. 



Äcanthias, Risso 



(Centrophoroides, Davis), (Fig. 47). As Centrophorus, but teeth in upper jaw 

 as in lower jaw. Upper Cretaceous, Sahel Alma, Mount Lebanon {Centro- 

 phoroides latidens, Davis). Tertiary {A. radicans, Probst) and Recent. 



Centrina, Cuv. Pliocene and Recent. 



Scymnus, Cuv. (Fig. 48). No dorsal fin spines. Upper teeth small, 

 pointed ; lower teeth much larger, broad and compressed, triangulär, erect or 

 only slightly inclined laterally. Eocene to Recent. 



Echinorhinus, Blainv. {Goniodus, Ag.) Pliocene and Recent. 



Grundlage des Baiies und der Entwickelung ihrer Wirbelsäule. Jena, 1879, with Appendix, 1885. 

 — Malier, J., and Henle, J., Systematische Beschreibung der Plagiostomen. Berlin, 1841. — Jaekel, 

 0., Die eoeänen Selachier vom Monte Bolca. Berlin, 1894. — Noetling, F., Die Fauna des samläii- 

 dischen Tertiärs (Abhandl. geol. Specialk. Preussen, vol. VI. pt. 3), 1885.— iVoös^, Beiträge zur 

 Kenntniss der fossilen Fische aus der Molasse von Baltringen (Württemb. naturw. Jahresh.), 1874. 

 1877, 1878, and 1882. 



