REPRODUCTION AND GROWTH 279 



in a Lutraria valve within which a batch of eggs had been 

 deposited but had disappeared, leaving traces of their 

 former presence in the shape of oval impressions. Occu- 

 pying the same shell was the Nudibranch Cahna glaucoides 

 (which had first spawned) and the observer thinks it almost 

 certain that the fish eggs had been devoured by the Nudi- 

 branch, which has been recorded as commonly associated 

 with goby and blenny eggs and varying in colour so as to 

 resemble the eggs which it apparently preys upon. 



Of the several species of goby frequenting our coasts, 

 the rock-goby, Gobitis paganelliis , is the one most frequently 

 encountered, being usually abundant among rock pools and 

 under stones between tide-marks. Breeding takes place in 

 spring, and the ova, regularly fusiform in shape with pointed 

 apex, are most commonly laid on the under side of an over- 

 hanging rock or stone and there guarded by the mate until 

 they hatch ; any suitable shelter, however, such as a shell 

 or old tin, probably serves for breeding purposes (Holt and 

 Byrne, 1901). 



Another species, Gohius ruthensparri, is frequent among 

 beds of Laminaria and Zostera. The breeding season extends 

 from April to August, during which period there is a constant 

 succession of broods. The eggs are pear-shaped with a 

 somewhat pointed apex, and seem to be laid upon any 

 sheltered and fairly smooth surface, e.g. inside the " bulbs " 

 of Laminaria hulhosa (Holt and Byrne, loc. cit.). 



Other gobies with more or less similar breeding habits 

 are found frequenting estuaries, e.g. the black goby {G. 

 niger) and the common or freckled goby (G. minutus). A 

 notable feature in the breeding of these gobies, apart from 

 the care of the ova by the male, is the fighting between 

 rival males, which in the case of the last-named species at 

 least is said to be so furious as not infrequently to result 

 in the death of the weaker fish, though perhaps as much from 

 exhaustion as from wounds (Holt and Byrne, loc. cit.). 



The eggs of the gunnel have already been noticed ; those 

 of its relative the Shanny {Blennius pholis) are ovoid in shape 

 with flattened under side (Hefford, op. cit.), and are attached 



