Teleostei — Acanthopterygii. 39 



Clay of Sheppey and the Lower Tertiaries of the Continent. To Table-case, 

 the latter belong Phyllodm (Fig. 76) and Phanjngodopilus (Xum- No - 53 « 

 mopalatus), and of the first-named genus the collection now com- 

 prises nearly all the type-specimens described in Prof. Cocchi's 

 Monograph on these fishes. Phyllodm is so called on account of 

 the leaf-like shape of the entire pharyngeal dentition, and the 

 separate teeth composing this are very thin and constantly replaced 

 by vertical successors, which are arranged in little piles beneath 

 the functional ones. 



The remarkable fragments of dentition from the London Clay, 

 known as Egertonia, and those from the Bracklesham Beds termed 

 Platylcemus, are also supposed to be referable to extinct Pharyngo- 

 gnathi. Taurinichthys, from the French Miocene, is also placed here. 



Suborder IV. — Acanthopteeygii. 



The Acanthopterygians are characterized, as their name denotes, Wall-cases, 

 by the almost invariably spinous character of a number of the rays os * t0 

 in the front part of the dorsal fin, and generally in the pelvic and ^ able "^ ases ' 

 anal fins. Nearly all, moreover, have the pelvic fins situated os ' ° ' 

 very far forwards, so as to become "thoracic." The air-bladder, 

 when present, is not connected by an open duct with the gullet, 

 in the adult. 



This suborder is divided into a great number of families, and all 

 the more important appear to be represented in the fossil state. 



The Indian freshwater Ophiocephalida are discovered in the Table-case, 

 Siwalik strata of that countrv. 



The Fistulariida, or " Flute-mouths," which have been aptly 

 described as " gigantic marine sticklebacks," are first known from 

 the Eocene formation. Fossil remains of the two living genera, 

 Fistularia and Aulostoma, occur at Monte Bolca and in the Slates 

 of Canton Glaris ; and Aicliscops, another existing form, has been 

 found at Padang, in the Tertiary Lignites of the Island of Sumatra. 

 The Monte Bolca deposits also yield two extinct genera, Uroxphen 

 and Phamphosus : the latter has an immense spinous ray, denticu- 

 lated behind, inserted on the nape, well shown in the specimen in 

 the case. 



The Mugilidce (" Grey Mullets ") are represented by Mugil itself 

 in the Upper Eocene of Aix in Provence ; and the closely-allied 

 AtherinidcB in the corresponding beds of Monte Bolca, by Mesogaster. 



The great voracious "Barracudas" (Spfiyranida) of the West Table-case, 

 Indies and other tropical seas have small representatives at Monte ° - 

 Bolca. It is quite possible, too, that Cladocyclus, with large cycloid 

 scales, from the Brazilian and European Cretaceous, is rightly 

 associated with the same family. 



Pterj/gocephalm, from the Eocene of Monte Bolca, seems to repre- 

 sent the "Blennies" (Blmiida): extinct species of " Gobies ' ; 

 ( Gooiida) are also found in the same formation, and in the Infusorial 

 Earth of Oran, Algeria. 



