HALOSAT7EIDJ3. 
163 . 
account of the osteology and the anatomy of some of the soft parts- 
of the type genus is given by Giinther \ 
Genus ECHIDNOCEPHALUS, W. von der March. 
[Zeitschr. deutsch. geol. Gesell. vol. x. 1858, p. 247.] 
An imperfectly known fish from which the existing genus HaU- 
saurus is not yet clearly distinguished. The dentition, cheek-plates, 
and pectoral fin are unknown, while the number of rays in the 
dorsal and pelvic fins is slightly less than is usual in the recent 
genus. Eranchiostegal rays about 12 in number. Vertebral centra 
very short and numerous as far as the middle of the caudal region, 
marked with delicate longitudinal striae. Dorsal fin with two 
simple, and about six branched rays, arising behind the pelvic pair 
and in advance of the anal, which is much extended and not 
differentiated from the caudal. Scales of lateral line thickened and 
apparently enlarged. 
Echidnocephalus troscheli, W. von der Marck. 
1858. Echidnocephalus troschelii, "VV. von cler Marck, Zeitschr. deutsch. 
geol. Gesell. vol. x. p. 247. 
1858. Echidnocephalus tenuicaudus^ W. von der Marck, ibid. p. 248. 
[Imperfect fish ; Academy of Miinster.] 
1863. Echidnocephalus troscheli, W. von der Marck,. Palseontogr. vol. xi. 
p. 55, pi. viii. fig. 1. 
1863. Echidnocephalus tenuicaudus, W. von der Marck, ibid. p. 56, 
pi. viii. figs. 2, 3, pi. xiv. fig. 1. 
. 1868. Echidnocephalus troscheli, W. von der Marck, loc. cit. vol. xv. 
p. 288. 
1873. Echidnocephalus troscheli., W. von der Marck, loc. cit. vol. xxii. p. 62. 
1897. Echidnocephalus troscheli, A. S. Woodward, Proc. Zool. Soc, 
^ p, 268, pi. xviii. 
Type. Imperfect distorted fish; Academy of Munster. 
The type species, attaining a length of about 0’3. Length of 
head with opercular apparatus apparently twice as gTeat as the 
maximum depth of the trunk, and equal to the distance between 
the clavicle and pelvic fins. Vertebral column as far as the middle 
of the caudal region comprising eighty short and deep centra; 
those beyond being relatively longer and less ossified. Pelvic fins, 
each with about 6 rays, arising midway between the pectoral arch and 
the anal fin ; dorsal fin short and deep, arising nearly opposite the 
^ A. Giinther, Deep Sea Fishes, ‘Challenger’ Eep.—Zool. vol. xxii. (1887), 
p. 232, pi. lx. figs. 1-8. 
