384 
CROSSOPTERYGII. 
Type. Scales and head-bones ; collection of Janies Thomson, Esq., 
Glasgow. 
Proportions of hones and scales, so far as known, resembling 
those of the type species. Ganoine covered with numerous small, 
closely-arranged, blunt tuberculations. 
Form. § Log. Coal-Measures : Lanarkshire, Northumberland, and 
Staffordshire. v ‘ * 
P. 4590. Left mandibular ramus, 0*135 in length, but imperfect 
anteriorly and exhibiting only the bases of the teeth : 
also an associated dermal plate and scale; Low Main 
Seam, Newsham, near Newcastle-upon-Tyne. 
Enniskillen Coll. 
P. 5494, P. 5137. Hinder portion of a similar mandibular ramus 
and a fragment; Newsham. Of the first specimen, a 
portion of the ornament is shown, five times the natural 
size, in PI. XIII. fig. 5. 
Presented by William Dinning , Esq., 1888. 
Megalichthys intermedins, sp. nov. 
1866. Rhomboptychins, J. Young (ex Huxley, MS.), Quart. Journ. Geol. 
Soc. vol. xxii. pp. 597, 604, woodc. figs. 1, 2. [Imperfect fish; 
Andersonian Museum, Glasgow.] 
(?) 1870. Megalichthys rugosus, J. Young, Rep. Brit. Assoc. 1869, 
Trans. Sect. p. 102. [Specifically indeterminable decorticated 
bones; collection of James Thomson, Esq., Glasgow.] 
1875. Rhomboptychius., J. Ward, [Proc.] N. Staffs. Nat. Field Club, 
p. 230, fig. 6. 
(?) 1875. Megalichthys rugosus, J. Ward, ibid. p. 229. 
1890. Megalichthys rugosus, Woodward & Sherborn, Cat. Brit. Foss. 
Vertebrata, p. 118. 
1890. Rhomboptychius, J. Ward, Trans. N. Staffs. Inst. Mining Engin. 
vol. x. p. 166, pi. ii. figs. 6, 24, pi. viii. fig. 9. 
Type. Portions of head ; British Museum. 
A species attaining a somewhat larger size than the type. Man¬ 
dible elongated, not less than five times as long as deep; posterior 
expansion of maxilla relatively deep ; larger teeth smooth or finely 
striated, often transversely banded, and sometimes with one or two 
rings of slight, vertically elongated indentations. Each of the pair 
of jugular plates about two and a half times as long as broad, 
rounded or obliquely truncated posteriorly. Ring-vertebrae much 
more slender than in M. hibberti; superficial ganoine upon the 
