110 CONTEIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 
occipital and nuclial regions, wliich are armed with bony bucklers. 
Marine cat-flsbes. Species very numerons in the tropical seas. This 
group has been divided into many genera, the value of which we are 
nnable to determine. Onr common species is not a typical Arins^ but the 
genus to which it belongs has not been i^roperly defined. (From Ari 
gagora, the Bengalese name of the typical species.) 
a. Teeth all villiform, in a large rounded patch on each palatine and a small one on 
each side of the vomer, these patches all distinct ; posterior buckler small. 
(Ariopsis* Gill.) 
no. A. feBis (Liund) J. & G. — Sea Cat-fish. 
Steel-blne, sides and belly silvery. Body rather elongate, not com- 
pressed, tajiering into the slender tail. Head snbconic, depressed, flat- 
tish above. Maxillary barbel nearly’ as long as the head. Month small. 
Eye moderate, jnst in front of the middle of the head. Gill membranes 
broadly united, partly joined to the isthmus, forming a narrow, free fold 
across it. A small, bony, grannlated bnckler, broader than long, in front 
of base of dorsal spine ; then a much larger nnchal shield with a me- 
dian keel, and a still larger occipital shield with a median furrow. A 
low fleshy keel along the back. Humeral process nearly half the length 
of the pectoral spine. Caudal deeply forked, the nipper lobe the longer. 
Head 3| ; depth 5. D. I, 7, its spine not filamentous, serrate in front ; 
P. I, 6; A. 16. L. 24 inches. Cape Cod to Florida; common south- 
ward. ' 
(Silurus fells Linn^, Syst. Nat.: Ai'ius milherti Cuv. & Val. xv, 74: Arim milherti 
Gunther, v, 155.) 
111. A. eqiiestras Baird & Girard. 
Similar, but with the spines higher and the maxillary barbels much 
longer, reaching to the middle of the pectorals. Pectorals reaching to 
last ray of dorsal. Dentition and character of the ceplialic bucklers 
undescribed. Head 4. D. I, 7; A. 16; P. I, 9. Coast of Texas; a 
doubtful species. 
(Baird & Girard, Proc. Acad. Nat. Sci. Phila. 1855, 26; Giiuther, v, 173.) 
58.— tELURICHTIIYS Baird & Girard. 
Sea Cat-Jislies. 
{Aihirichfhys Baird & Girard, Proc. Acad. Nat. Sci. Phila. 1854,26: type Silurus mari- 
nus Mitchill. ) 
Body rather elongate, little compressed. Head depressed, broad 
above. Mouth large, the upper jaw the longer. Teeth all villiform ; those 
on the vomer and palatines forming a more or less perfectly crescent- 
* Ariopsis et Notarius Gill, Proc. Acad. Nat. Sci. Phila. 1863, 171 : type Arius milberti 
C. & V. ^Arius ; b'tptg, appearance.) 
