﻿246 SIRENOIDEI. 



The fcjpe species. Breadth of snout at anterior nares about 0*06 ; 

 tlie inferior overturned margin very broad mesially, deeply notched 

 by the narial openings laterally, flat, with few very coarse puncta- 

 tions, and large tubercles upon its posterior edge. 



Form. $ Lot. Unknown. 



44627. Type specimen, incidentally mentioned under the name of 

 Megalichihys hibberti by Agassiz, Poiss. Foss. vol. ii.pt. ii. 

 p. 91. History unknown. 



A smaller rostrum than the type specimen of G. woodwardi, with 

 a narrower inferior overturned margin and without lateral narial 

 excavations, is described as GanorJiynchus beecheri, J. S. jNewberry, 

 Palasoz. Fishes IS". America (Hon. U.S. Geol. Surv. no. xvi. 1889), 

 p. 95, pi. xix. fig. 2. This fossil was obtained from the Chemung 

 Group (Upper Devonian) of Warren, Pennsylvania, and is now in 

 the Museum of Columbia College, Xew York. 



The following genera and species are also regarded by A. Fritsch 

 as founded upon the dermal head-bones of Dipnoan fishes : — 



Gompholepis panderi, J. Barrande, Syst. Silur. Boheme, vol. i. 

 suppl. i. (1872), p. 644, pi. xxviii. figs. 1-3 ; A. Fritsch, Fauna der 

 Gaskohle, vol. ii. (1888), p. 87, fig. 166, woodc. — Upper Silurian 

 (Stage 6 g 1); Chotec, Bohemia. [Royal Bohemian ^Museum, 

 Prague.] 



Dipnoites perneri, A. Fritsch, Fauna der Gaskohle, vol. ii. (1888), 

 p. 86, fig. 1$3, woodc. — Upper Silurian (Stage G g 3) ; Hlubocep, 

 near Prague. [Royal Bohemian Museum.] 



Family PHANEROPLEURIDJE. 



Cranial roof-bones numerous ; margin of mouth, above and below, 

 provided with a series of conical teeth ; jugular plates present. 

 Caudal fin diphycercal. Scales cycloid. 



Synopsis of Genera. 



Ajoal fin separate Tlianeropleuron (p. 247 ). 



Anal fin continuous with caudal Uronemus 1 (p. 249). 



1 Since these pages were in type, Dr. K. H. Traquair (Proc. Eoy. Soc. Ecliob. 

 vol. xvii. 1890, p. 393) has expressed his opinion that Uronemus represents a 

 distinct family, the Uronemidse. The upper dental plates are stated to be 

 replaced by mere granulations, but no details are as yet forthcoming. 



