23O CALIFORNIA ACADEMY OF SCIENCES. 



20. Dactylagnus mundus Gill. Plate xxxiii. 



I present a figure of this species from a specimen ob- 

 tained by Dr. Gilbert while with the Albatross. The 

 genus is a valid one, well separated from Dociyloscopus. 



Family GOBIESOCID^;. 



21. Bryssetaeres pinniger (Gilbert). Plate xxxiv. 



Gobiesox pinniger Gilbert, Proc. U. S. Nat., 1S90, 94. Puerto Ke- 

 fugio, Gulf of California. 

 This species is the type of a distinct genus, Bryssetczres 

 Jordan & Evermann, distinguished from Gobiesox by the 

 long dorsal fin. The vertebrae are 26, as in Gobiesox. 

 The plate here given is from one of the type specimens. 

 The name /S/»Wo?, sea-urchin; yraipos, comrade, al- 

 ludes to the brotherhood existing between the Cling- 

 fishes and the Sea-urchins in the rock pools. 



22. Arbaciosa humeralis (Gilbert). Plate xxxv. 



Gobiesox humeralis Gilbert, Proc. U. S. Nat. Mus., 1890, 95. 

 Puerto Kefugio. 



This species, with its allies zebra, eos, rhessodon, etc., 

 differs from Gobiesox in the serrated teeth. It may be 

 made the type of a distinct genus, Arbaciosa Jordan & 

 Evermann. 



The name is given in allusion to the close association 

 in the rock pools between the Sea-urchins and the species 

 of this genus. This relation is especially close between 

 the Sea-urchin, Arbacia stellata and Arbaciosa zebra. 



23. Arbaciosa rhessodon (Rosa Smith). Plate xxxvi. 



I present a figure of this interesting species from a 

 specimen from San Diego. 



24. Arbaciosa eos (Jordan & Gilbert). Plate xxxvii. 

 I here present a figure of a specimen from Mazatlan. 



