258 
PACIFIC SCIENCE, Vol. VI, July, 1952 
copulation the male dropped to the bottom, 
but did not lie there quietly as before. In- 
stead, the tail was arched high away from the 
substrate and the mouth held open (Fig. \e) . 
Convulsive movements persisted for about 
10 minutes, subsiding gradually. 
On April 5, the male was removed from the 
aquarium. The female which had spawned 
and copulated on March 23, spawned again 
on April 9 and again on May 6. Both clusters 
deposited after removal of the male proved 
fertile and developed normally. The female 
that had spawned and copulated on March 
27, spawned again on April 21. Only about 
one half of the eggs of the spawning of April 
21 developed. The remainder appeared to be 
infertile. The subsequent history of the eggs 
and the development of the larvae have al- 
ready been described (Morris, 1951). 
The two females measured 85 and 98 mm. 
in total length. During the period of February 
27 to May 6, it is estimated that the total 
number of eggs laid by both was between 
8,000 and 9,000. This estimate is based on the 
sizes of the clusters and on a count previously 
made on an egg cluster of the same species. 
CONCLUSIONS 
On both occasions of observed copulation, 
spawning preceded copulation by several 
minutes. The females continued to lay fertile 
eggs for several weeks after copulation. These 
two characteristics are reminiscent of the 
breeding behavior of some of the ovovivi- 
parous fresh- water aquarium fishes. 
The sharp difference observed in egg color 
suggests that this character is dictated by en- 
vironmental conditions and possibly to a 
great extent by the nature of the food. 
The fecundity of this species and the ease 
with which it is kept in aquaria indicates that 
it would be a very convenient subject for 
laboratory studies. 
REFERENCE 
Morris, Robert W. 1951. Early develop- 
ment of the cottid fish, Clmocottus recalvus 
(Greeley).' Calif. Fish and Game (3): 
281-300, 28 figs. 
i 
f. ^ 
