PACHYC0RMID2E. 
413 
P. 1482 a. Another similar specimen; English Chalk. 
Egerton Coll. 
25846. Fragment of fin ; Chalk, Sussex. Dixon Coll. 
49817. Another small fragment; Chalk, Amberley. Capron Coll. 
The following specimens are more doubtfully assigned to Proto¬ 
sphyrcena :— 
4077. Anterior portion of fin described and figured by Agassiz 
(op. cit. vol. iii. p. 59, pi. x. b. fig. 18) under the name of 
Ptychoclus ; Chalk, Lewes. Mantell Coll. 
25846 a. Fragment figured as Ptychoclus in Dixon’s Geol. Sussex, 
pi. xxxi. fig. 14 ; Chalk, Sussex. Dixon Coll. 
P. 7573. Very imperfect pectoral fin showing seven basals and 
other bones ; English Chalk. History unhioivn. 
The so-called Ptychodus articulcitus, Agassiz (op. cit. vol. iii. p. 58, 
pi. x.a. figs. 5, 6) seems to be a fragment of the caudal fin of 
Portheus or an allied fish. The appearance of a wavy margin given 
in Agassiz’s figure is imaginary. 
The following specimen probably belongs to the family Pachy- 
cormidse, if not to the genus Protosphyrcena itself :— 
49531. Middle portion of caudal region noticed in Ann. Mag. Nat. 
Hist. [6] vol. xiii. (1894), p. 512; Upper Cretaceous, 
Sahel-el-Alma, Mt. Lebanon. There are no traces of 
vertebral centra, but the arches are very numerous and 
well ossified, somewhat expanded at the base. Remains 
of a dorsal fin occur in advance of a smaller anal. Fos¬ 
silized remains of the muscular fibres are also conspicuous. 
jr An imperfect and abraded rostrum from the Cretaceous (Niobrara 
Group) of Kansas is also referred to this genus under the name of 
Erisichthe ziphioide s by E. D. Cope, Bull. U.S. Geol. Surv. Territ.^^^U^ ^ J 
vol. iii. (1877), p. 823. ^ Fragments of jaws from the Cretaceous ^,' x 
North Carolina are provisionally placed here (Portheus cingidcitm^fr^o^,/^^/^ 
E. D. Cope, Proc. Acad. Nat. Sci. Philad. 1872, p. 281, and in 
Kerr’s Bep. Geol. Surv. N. Carolina, 1875, Append. B, p. 32 
Erisichthe ayigulata, E. D. Cope, Vert. Cret. Form. West, 1875, 
p. 2/5). f 
Pectoral fins of undetermined species- of Protosphyrcena were 
