REPRODUCTION AND GROWTH 253 



with its head close to a mass of ova placed on the seaward 

 edge of a stone, close to low-water mark. The stream of 

 water at low tide was not sufficient to float the fish, which 

 accordingly had to lie on its side for a considerable period 

 twice daily, under a warm sun, with the upper portion of 

 its gill region out of water. The animal, however, was 

 oriented in such a way that the current of the runlet flowed 

 directly into its mouth, and thus, notwithstanding a slight 

 acceleration of the action of heart and gill-apparatus, 

 sufficient aeration was obtained. In this position the fish 

 was observed at low tide for a period of five or six weeks. 

 When, on one occasion, it was removed a couple of yards 

 from the eggs and placed upon a stone it wriggled actively 

 into the water, at once rushed to the ova and assumed its 

 former position with the snout almost touching the eggs. 

 The same ensued when the fish was placed in the runlet at 

 a somewhat greater distance. M'lntosh states that the 

 solicitude of the males for the ova which they have under 

 charge was further illustrated by the occurrence early in 

 May of a heavy sea, which swept masses of ova from their 

 positions all along the rocks. As soon as the water became 

 calm again " numerous anxious males, like * pilgrims,' 

 were seen by the laboratory attendant (who had been familiar 

 with the sites) seeking for their lost charges. Many of 

 these masses of eggs were found on the beach, so that the 

 statement is probable." 



Not infrequently the shore collector will find a mass of 

 eggs, about the size of a walnut, closely invested by the body 

 of the male butterfish or gunnel {Centronotus gunnelliis) (see 

 Fig. 15). Storrow (191 5) has observed the behaviour of one 

 of these fishes, which was found beneath a stone in an inch 

 and a half of water with another gunnel close by. When 

 the ova were moved three inches the fish followed and 

 again coiled round them and, although touched, refused to 

 move. Eventually it had to be pushed into deeper 

 water. Meanwhile, the second fish coiled round the eggs 

 and did so again even after they were removed two feet. 

 The eggs were on the point of hatching. Elmhirst (191 5) 



