212 
ANTIARCH A. 
and is bordered below by a large membranous caudal fin (PI. YI. 
fig. 3, sc) of uncertain shape. There are no pelvic fins, the 
determination of their presence by Egerton 1 being founded upon a 
mistake 2 . 
Pterichthys milleri, Agassiz. 
[Plate Y. figs. 2-7.] 
1841. Pterichthys milleri, H. Miller (ex Agassiz), Old Red Sandstone, 
p. xxii, pis. i. & ii. 
1844. Pterichthys milleri and P. latus, L. Agassiz, Poiss. Foss. vol. ii. 
pt. i. p. 802 (names only). 
1844. Pterichthys latus, L. Agassiz, Poiss. Foss. \ . G. R. p. 12, pi. iii. 
figs. 3^ 4. [British Museum and F err e s Museum.] 
1844. Pterichthys milleri, L. Agassiz, ibid. p. 15, pi. i. figs. 1-4J. 
1848. Pterichthys quadratics, Sir P. Egerton, Quart. Journ. Geol. Soc. 
vol. iv. p. 313, pi. x. [Geological Society of London.] 
1848. Pterichthys latus, Sir P. Egerton, ibid. p. 312. 
1855. Pterichthys latus , F. M‘Coy, Brit. Palseoz. Foss. p. 600. 
1888. Pterichthys milleri, R. H. Traquair, Geol. Mag [3] vol. v. p. 509. 
Type. Head, trunk, and base of tail, ventral aspect; Edinburgh 
Museum. 
The type species. Inferior surface of carapace broadly ovate ; 
tail about equal in length to the trunk. Pectoral appendages two- 
thirds as long as the trunk, not expanded, tapering. 
Form. $ Loc. Lower Old Red Sandstone: Cromarty, Banffshire, 
and Nairn shire. 
P. 6259. Paper model of carapace, made by Hugh Miller. 
Egerton Coll. 
(i.) Cromarty (typical P. milleri). 
19804. Imperfectly preserved small specimen in counterpart. 
Purchased , 1845. 
?. 654. Imperfect similar specimen, wanting head ; bearing auto¬ 
graph of Hugh Miller. Egerton Coll. 
P. 3213. Small crushed trunk and head, in counterpart. 
Enniskillen Coll. 
21974. Imperfect head, trunk, and pectoral appendages, ventral 
aspect, as large as the typical P. latus. Purchased, 1848. 
1 Quart. Journ. Geol. Soc. vol. xvi. (1860), p. 127. 
2 R, JI. Traquair, Geol. Mag. [3] vol. v. (1888), p. 509. 
