156 SILURIB^E. 



spine is small. Dorsal spine rather strong, three-fii'tlis as long as 

 the head, granulated in front and serrated behind. Adipose fin 

 shorter than the dorsal. Pectoral spine serrated interiorly and to- 

 wards the point on the outer edge. 

 Southern States of North America. 



a-b. From 11-12 inches long. From the Haslar Collection. 



31. Arius rugispinis. 



Arius rugispinis, Cuv. §- Val. xv. p. 77 ; Kner, Sitzgsber. Wien. Acad. 

 xxvi. p. 388. 



D. 1/7. A. 21. P. 1/11. 



The length of the head is one-fifth of the total (with the caudal). 

 The occipital process is longer than broad, its length being two-fifths 

 of that of the remaining portion of the head. Eye small, its fUameter 

 being one-fifth of the width of the interorbital si)ace. Head coarsely 

 granulated above ; basal bone of the dorsal spine small. Teeth on 

 the palate in two widely separate, rather small, ovate jjatches. The 

 maxillary barbel extends to the middle of the opercle. The spines 

 are very strong, entirely granulated ; that of the dorsal fin is scarcely 

 denticulated. Adipose fin nearly as long as the anal. ( Val.) 



Cayenne. (Specimens from 12-15 inches long.) 



Anus dieperinki, Bleek.Versl. & Mededeel. Akad.Wetensch.1862, 

 xiv. p. 375, is perhaps identical with the above species ; its head is 

 longer than it would appear to be in A. ruc/isjnnis, according to 

 Valenciennes's descriijtion, being one-fourth of the total length in 

 the specimen described by Bleeker. 



32. Arius phrygiatus. 



Arius phrygiatus, Cuv. Sf Val. xv. p. 79. 



D. 1/7. A. 19. P. 1/11. 



The length of the head is one-fifth of the total (with the caudal) ; 

 the diameter of the eye is one-fifth of the width of the interorbital 

 space. Occipital process much longer than broad, its length being 

 one-third of that of the remaining portion of the head. The maxil- 

 lai-y barbel extends to the middle of the opercle. Teeth on the palate 

 villiform, forming two widely separate ovate patches. Spines of the 

 fins rather strong^ finely serrated along both edges. Adipose fin as 

 long as the anal. (Val.) 



Cayenne. The typical specimen, 61 inches long, is said to be in 

 the Leyden Museum, but it could not be found by Bleeker when he 

 examined the Siluroids of that genus. 



