350 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



Gilbert and myself iu rock pools, at Santa Barbara, Cal., in the winter 

 of 1880. It was at first supposed by us to be identical with Blennius 

 gentilis Girard, a species of which we obtained no adult specimens. 

 Numerous specimens of Isesthes (jilberti have been distributed under the 

 name of Hi/pleurochilus gentilis (number 2G917, U. S. Nat. Mus.). Four 

 specimens from Santa Barbara (26916) are the types of the present 

 description ; all of them are males. 



The following description of specimens of Isesthes gentilis may be 

 compared with the foregoing. 



Head 3| in length {U with caudal); depth 4 (4|-). D. XIII, 17; A. 

 11, 19. Length (26645) 3f inches. 



Body rather robust, deep and compressed, the head large, very bluntly 

 and evenly rounded in profile, more obtuse and more evenly curved 

 than in I. giJberti, the snout shorter, about equal to eye, 4^ in head. 

 Mouth rather small, terminal, the maxillary reaching to opposite middle 

 of eye, its length 3 iu head. Teeth subequal, the hindmost on each side 

 of upper jaw shorter than the others, and a little apart from them but 

 not forming "a small canine" as stated by Girard. 



Superciliary tentacle long and simple in all specimens examined, its 

 length about 3 in head. (Tentacles much smaller in the female, accord- 

 ing to Steindachner.) 



Gill-opening extending downward not quite to lower edge of pectoral, 

 its length (vertical) 2^ in head. Lateral line with only the straight 

 anterior portion developed, not curved downward posteriorly. 



Dorsal fin continuous, with scarcely a trace of emargination between 

 the spinous and soft parts. Dorsal spines comparatively low and flex- 

 ible, much less strong than in I. gilberti, the longest spines 3 in head; 

 longest soft rays If. Caudal free from dorsal and anal. If in head. 

 Yentrals 1| in head ; pectorals 1^. 



Coloration, in spirits, brown, the whole body closely mottled and 

 blotched with darker brown, so that the light ground color forms, 

 especially anteriorly, light reticulations around darker spots. On the 

 head the dark spots are small and close together, smallest anteriorly, 

 the lower parts of the head being immaculate. Extending from the 

 curve of the preopercle downward, across the interopercle and branchial 

 region, is a sharply defined white bar (said to be golden-yellow in life), 

 edged with black. Behind this and parallel with it across subopercle and 

 isthmus is a similar bar. These bars (which, according to Steindachner, 

 are characteristic of the male) are present iu all specimens examined, 

 A few pale spots or bars in front of these. Back with about 6 dusky 

 cross-shades; below each of these is an oblong dark blotch, the anterior 

 placed along the lateral line, all together forming an interrupted dark 

 stripe. A similar dark stripe near the median line of the body, inter- 

 rupted by some pale blotches. Fins all blotched and spotted with light 

 and dark colors, but without distinct markings (a blue spot on front 

 of dorsal in life, according to Steindachner). Ventrals and anal nearly 



