102 SILURIDiE. 



pectoral spine very conspicuously so ; caudal fin moderately forked. 

 {Girarcl.) 



Source of the Eio Pecos. 



Pimehdus hammondii, Abbott, Proc. Acad. Nat. Sc. Philad. 1860, 

 p. 568, appears to have a comparatively smaller head than P. lupus, 

 constituting somewhat less than one-fifth of the total length, whilst 

 it is said to be one-fourth in P. lupus. — Kansas. 



Ictalurus simpsonil, GiU, Proc. Best. Soc. Nat. Hist. 1862, p. 43, 

 appears to me to be identical with P. hammondii. 



10. Amiurus cauda-furcatus. 



Pinielodus cauda-furcatus, Lesueur, Mem. Mu^. d'Hist. Nat. 1819, v. 



p. 152 (not P. furcatus, Cuv. & Val.). 

 fm'cifer, Cuv. S, Val. xv. p. 139 ; HyiiJ, Dcnhschr. Acad. Wiss. Wien, 



1859, xvi. p. 16; Kner, Sitzi/sher. Acad. Wins. JJ'iiti, xxvi. p. 421. 

 olivaceus, Girard, in V. S. Pacif. P. P. Exped. Fish. p. 211. pi. 41. 



tigs. 1-3, and pi. 42 (iucoiTect). 

 gTaeiosus, Girard, in Proc. Acad. Nat. Sc. Philad. 1859, p. 161. 



B. 8. D. 1/6. A. 26-27. P. 1/9. Yert. 13/29 (C. Sf V.), 



15/30 {Hijrtl). 



Head one-fourth longer than broad ; the maxillary barbels extend 

 beyond the end of the head. Dorsal spine as long as the head with- 

 out snout ; pectoral spine stronger and rather longer than that of 

 the dorsal fin, denticulated interiorly. Adipose fin short; caudal 

 deeply forked. 



Ohio, Missouri, and Ai'kansas Rivers. Surinam (?). 



((. Half-grown : skin. Ohio Canal. From Dr. ParneU's Collection. 

 h. HaK-grown : skin. Portsmouth, Ohio Eiver. From Dr. ParneU's 



Collection. 

 c-d. Adult and young : bad state. 



11. Amiurus meridionalis. 

 D. 1/6. A. 28-29. P. 1/9. 



Head one-half or one-thii'd longer than broad ; the maxillary bar- 

 bels extend to the end of the head. The length of the dorsal spine 

 is somewhat less than that of the head without snout, and nearly 

 equal to that of the pectoral spine. Adipose tin short. 



The height of the body is one-fifth of the total length (without 

 caudal), the length of the head one-fourth or two-ninths. Snout 

 obtusely rounded, with the upper jaw longer than the lower. The 

 diameter of the eye is one-half or two-fifths of the extent of the 

 snout, and one-third or two-sevenths of the length of the postorbital 

 portion of the head. The band of maxillary teeth is five or six times 

 as broad as long. The outer mandilnilary barbels extend to the 

 posterior margin of the gill-membrane. The distance of the dorsal 

 spine from tiie snout is a little more than one-half of its distance 

 from the caudal fin ; it is finely serrated behind. The length of the 

 base of the adipose fin equals that of the dorsal. Caudal fin deeply 



