Cope.] 486 rune 7, 
Head less than one-fourth length. A. 20; eye 4.5 tim2s between orbits ; 
dorsal nearer adipose fin than muzzle. A. CONFINIS. 
Head as above; orbit 4 times between orbits; A. 23; dorsal nearer 
muzzle than adipose fin. A. HOYL 
aa Caudal furcate. 
Width of head from 4.6 times in length; eye large, 3 to 5 times in inter- 
orbital space ; barbels long ; caudal fin deeply forked. 
; A. LYNX. 
Head very wide, width 3.6 times in length; eye six times between 
orbits, barbels very short,-caudal not deeply furcate. 
A. LOPHIUS. 
AA Anal fin large; radii 24-5. 
Caudal emarginate ; pectoral spine not denticulate ; barbels reaching 
gill opening ; head wide as long. A. BOREALIS. 
Caudal deeply furcate ; head narrow, pectoral spine dentate, barbels to 
end of humeral process. A. NIVEIVENTRIS. 
Of other species of the genus, I have omitted A. puma Gird. A. natalis 
Les., and A. felis Agass, all belonging to section I, owing to the imper- 
fections in the descriptions. A. albidus Lesueur, is, I think, founded on 
adults of A. nebulosus Les. A. obesus Gill of which I have examined 
numerous specimens from Minnesota, two from the Miami, Ohio, and one 
from the Kiskiminitas River, in West Pennsylvania, I cannot distinguish 
from A. catulus Girard (U. 8. Pac. R. R. Rept. X). Of species adopted, 
A. catulus Girard, may be found eventually to be varieties of A. nebu- 
losus. The A. mispilliensis, A. lophius and A. niveiventris, are now de- 
scribed for the first time. 
77. AMIURUS PLATYCEPHALUS, Girard. 
Proc. Ac. Nat. Sci. Phila. 1859, 160. ; 
This well marked species approaches nearer the genus Hopladelus than 
any other Amiurus, in its elongate, flattened body and head, and in the 
_ large number (11) of its branchiostegal radii. It abounds in the Catawba 
and Yadkin Rivers, where it is justly valued as an article of food. 
Amiurus mispilliensis, Cope. 
Spec. nov. 
This species is related to the common A. nedulosus, but has a narrow 
muzzle, larger eyes and a ventral ray less than any other species of the 
section. Width of head 4.66 times in length; eye 3.25 times between 
orbits, maxillary beard extending beyond base of pectoral fins. Pectoral 
spine dentate, dorsal spine smooth. DI. 6; V.1.6; A. 21. Above entirely 
black ; below, white anterior to anal fin. The mental barbels blackish. The 
maxillary barbels extend to beyond base of pectoral fin, and the mentals 
to the branchiostegal margin. Entire length 8 in.; depth 1in. 8 lines. 
I took this specimen in the Mispillion Creek, a sluggish stream in the 
southern part of the State of Delaware. It doubtless occurs in similar 
streams in ‘‘the Peninsula.’’ 
