NOTES ON THE TIDE-POOL FISHES OF CALIFORNIA, WITH A DESCRIPTION 
OF FOUR NEW SPECIES. 
By ARTHUR WHITE GREEEEY, 
Teacher of Biology , San Diego State Normal School. 
This paper is based on collections made on several trips along the coast of Cali 
fornia from San Francisco Bay to Point Sur, in Monterey County, in 1897 and 1898. 
The fishes were taken exclusively in the tide-pools exposed at low water and were 
captured with small hand nets. .Calcium hypochlorite or ordinary chloride of lime 
(bleaching powder) was used with excellent effect for stupefying the fisbes in small, 
isolated tide-pools. The fishes were taken out as soon as they came to the surface 
and were killed in dilute alcohol or formalin. 
The following new species were obtained : Eximia rubellio , Rusciculus rimensis, 
Dialarchus snyderi , and Blennicottus recalvus , three of them representing new genera, 
Rusciculus, Eximia, and Dialarchus. One of these species, Dialarchus snyderi, is 
mentioned in the addenda of Jordan & Evermann’s Fishes of North and Middle 
America as Oligocottus snyderi, but it is now made the type of a new genus and is 
fully described and figured for the first time. The group of tide-pool cottoids, the 
allies of Oligocottus, are here subjected to a critical revision, in view of the confused 
state of the literature concerning them. 
The group of Gottidce of the type Oligocottus , comprising the genera Oligocottus , 
Blennicottus , Glinocottus, and Oxycottus , and the new genera Eximia, Rusciculus, and 
Dialarchus , is distinguished from the rest of the family by the separation of the gill 
membranes from the isthmus, the presence of palatine teeth, and either the entire 
nakedness of the body or the presence of only rudimentary, prickly scales. They are 
all strictly tide pool fishes of the Pacific coast, ranging from Bering Sea to Lower 
California aud never wandering far from shore. Each species inhabits, with surprising 
regularity, only certain kinds of tide-pools, its distribution depending almost entirely 
upon the character of the rocks aud the kind of algte present. They all imitate very 
closely the color of their surroundings, and two or three species show parallel color 
phases, each copying after a certain kind of alga. Thus, depending on these condi- 
tions of rock and plant life, there are along almost any part of the coast two or three 
zones of vertical distribution, one species inhabiting the deeper tide-pools, another 
the shallower, and so on, as will be seen by reference to the descriptions. Glinocottus 
analis offers a marked exception to these generalizations, however, as it is found in 
every kind of tide pool within its range. 
The first known species of this group were described by Girard as follows: Oligo- 
cottus maculosus in 18.56, 0. analis in 1857, and 0. globiceps in 1858. These last two 
species were made types of new genera by Gill in 1861, giving them the names Glino 
coitus and Blennicottus. These two genera of Gill were not recognized by Jordan A 
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