Jordan and Evermann. Fishes of North America. 2413 



903. XERERPES, Jordan & Gilbert. 

 Xererpes, JORDAN & GILBERT, Proc. Cal. Ac. Sci. 1895, 846 (fucorum). 



This genus differs from Apodichthys in the moderate size of the anal spine, 

 which is rounded and not channeled on its anterior edge, and in the small 

 size of its pectoral fins. The single known species lives in Fucus chiefly 

 above low -tide mark and may often be shaken out of half-dry mats of sea- 

 weed on rocks well above the water, (ge/aos, dry; epxyg, creeper.) 



2768. XERERPES FUCORUM (Jordan & Gilbert). 



Head 10 ; depth 9|. D. LXXXIII ; A. 35. Form and dentition as in Apo- 

 dichthys flavidus. Mouth very oblique, the maxillary reaching center of 

 pupil ; nape nearer front of dorsal than end of snout. Anal spine compara- 

 tively small, about length of head, transversely very convex in front, 

 and slightly concave or grooved behind, the pouch of skin at its base 

 little developed; pectorals very small, shorter than eye ; anal fin beginning 

 nearer tip of caudal. than tip of snout by about 3 times length of head. 

 Bright olive green or deep red, the color varying with the surroundings ; a 

 row of dark spots along axis of body, these sometimes with light-bluish 

 center, and connected by a very narrow dark streak; generally a dark 

 streak downward from eye, but no other markings about head. Length 

 6 inches. Monterey to Puget Sound; abundant in rock pools and bunches 

 of Fucus ; remarkable for its active movements. It is found mostly in 

 masses of Fucus attached to rocks between tide marks, and it is often found 

 at low tide at a considerable distance from any water, kept damp by the 

 masses of algae. Sometimes a dozen of them can be shaken from a bunch 

 of algae attached to a dry rock. It is, like the species of Xiphidion, very 

 active, moving over stones or sand, and showing less anxiety about the 

 presence of its native element than any other fish known to us. (fucorum] 

 of the Fucus or seaweed.) 



Apodichthys fucorum, JORDAN & GILBERT, Proc. IT. S. Nat. Mas. 1880, 139, Monterey 



(Coll. Jordan & Gilbert) ; JORDAN & GILBERT, Synopsis, 770, 1883. 

 Xererpes fucorum, JORDAN & STARKS, Proc. Cal. Ac. Sci. 1895, 846. 



904. ULVICOLA, Gilbert & Starks. 



Ulvicola, GILBERT & STARKS, Proc. TJ. S. Nat. Mus. 1890, 455 (tanctce-rosce). 



This genus is allied to Xererpes, but differs in having the opercle above 

 angle adnate to shoulder girdle, in the smaller size of the anal spine, and 

 especially in the entire absence of pectoral fins. ( Ulva, sea lettuce ; colo, 

 I inhabit.) 



2769. ULVICOLA SANCTjE-ROS^E, Gilbert & Starks. 



Head 10 in body; depth 13. D. XCVII; A. 1, 40; eye 4i in head; caudal 

 1|. Body elongate, as in Apodichthys, strongly compressed, upper profile 

 of head slightly convex, no construction at nape; mouth very small, 

 oblique, the maxillary reaching about to front of eye ; teeth very small in 



