59. ARIUS. 



157 



■y. Pacific species. 



33. Arius dasycephalus. 

 D. 1/7. A. 23. P. 1/11. 



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

 caudal), the length of the head two-ninths. Head small, broader 

 than high, its greatest width being four-fifths of its length ; snout of 

 moderate length, rounded, its extent being three-fifths of the mdth 

 of the interorbital space. The eye is situated much nearer to the end 

 of the snout than to that of the operculum ; its diameter is one-sixth 

 of the length of the head, and one-third of the width of the inter- 

 orbital space. Cleft of the mouth narrow. The teeth ^- — ^^^^ 

 on the palate are viUiform, and form a pair of separate, K^,^-—^-^ 

 transverse, quadrangidar patches, each of which is ^^ pp^ 

 broader than long, and again composed of two portions. ^^^ 



The maxiUary barbels extend to the middle, the outer of the man- 

 dible to the root of the pectoral fin. The crown of the head is 

 coarsely granulated, the gra- 

 nules forming two bands di- 

 verging in front and extend- 

 ing to the snout. There is a 

 pair of prominent, parallel, 

 granulated ridges along the 

 middle of the forehead, 

 reaching to between the nos- 

 trils. Occipital process tri- 

 angular, as broad at the base 

 as long, elevated into a ridge 

 along its middle ; basal bone 

 of the dorsal spine smaU, 

 crescent - shaped. Dorsal 

 spine of moderate strength, 

 three-fourths of the length of 

 the head, slightly serrated in 

 front and behind ; the first 

 soft ray is much longer than 

 the spine and higher than 

 the body. Adipose fin as long 

 as dorsal. Caudal deeply 

 forked, with the upper lobe 

 longest, one-fifth of the total 

 length. Pectoral spine rather 

 stronger, but scarcely longer, than that of the dorsal fin, serrated 

 along both edges. Ventral rather shorter than pectoral. Fins 

 blackish. 



Sandwich Islands. 



a. Eleven inches long. Oahu. From the Haslar Collection. — This 

 specimen is a pregnant female ; on opening the left ovarium 

 nine eggs may be seen, developed to the size of a small cherr)\ 



