462 
ACTISTOPTERYGTI. 
of moderate size^ consisting of delicate rays, distally bifurcated, with 
an anterior series of slender fulcra ; principal rays of pectoral tin 
unarticulated except near their distal extremity. Dorsal and anal 
tins triangular, partly or completely opposed ; upper caudal lobe 
slender, and caudal tin deeply forked, unsymmetrical. Scales 
large or of moderate size, more or less delicately sculptured; 
ridge-scales in advance of dorsal tin much enlarged. 
Rhadinichthys ornatissimus (Agassiz). 
I 860 . Palceoniscus ornatissimus, L. Agassiz, Poiss. Foss. vol. ii. pt, i. 
p. 92, pi. x. a. figs. 6, 8 ( non tigs. 5, 7). 
1877. Rhadinichthys ornatissimus, It. H. Traquair, Quart. Journ. 
Geol. Soc. vol. xxxiii. p. 559, and Proc. Roy. Soc. Edinb. vol. ix. 
p. 432. 
1877. Rhadinichthys lepturus, R. H. Traquair, Proc. Roy. Soc. Edinb. 
vol. ix. p. 437. [Imperfect fish ; Edinburgh Museum.] 
1890. Rhadinichthys ornatissimus, R. H. Traquair, Proc. Roy. Soc. 
Ediub. vol. xvii, pp. 391, 397. 
Type. Imperfect fish ; Edinburgh Museum. 
The type species, attaining a length of about 0-25. Head with 
opercular apparatus occupying about one-fifth of the total length; 
greatest depth of trunk immediately behind the operculum, and 
tail-pedicle narrow. Head - bones finely and closely striated. 
Paired fins small, the pectoral about one half as long as the head; 
dorsal fin arising slightly in front of the anal, shorter than the 
latter, both these fins with much excavated posterior margins. 
Scales of flank relatively large, somewhat deeper than broad. 
Scale-ornament consisting of sharp, delicate striae, mostly paralle 1 
with the superior and inferior margins, sometimes sigmoidally 
curved, with punctures in the intervening furrows; posterior 
margin serrated. 
Form. 4' Log. Calciferous Sandstones : Midlothian and Eifeshire. 
P. 3439. An imperfectly preserved fish wanting the head, and an 
imperfect caudal region ; Burdiehouse, near Edinburgh. 
Enniskillen Coll. 
P. 1000. Remains of small trunk: Grauton, near Edinburgh 
Egerton Coll. 
41129. Imperfect small fish ; (?) Burntisland, Fifeshire. 
Bryson Coll. 
