174 Part III. — Twenty -fourth Annual Report 



readily enticed by holding mussels in front of him under the surface of 

 the water, when he would swim after them as they were slowly with- 

 drawn ; but, though very fond of mussels, his fear of the other male 

 usually subdued his appetite before he had gone very far, and he turned 

 back. 



Whenever the guarding male saw his late opponent moving, even a 

 comparatively little way from his retreat, he rushed at him with the 

 utmost fury — I was not previously aware that so clumsy aud usually 

 sluggish a fish could swim so fast — and the other male made off with equal 

 speed, and often attempted to jump out of the water, or was partly 

 knocked out. On such occasions so much commotion was made that 

 waves were created in the tank and the other fishes were alarmed. These 

 were the only occasions that the guardian left the eggs for a few moments. 

 The animosity was kept up during the whole period of the experiment, a 

 fact which is of some interest. 



The females took no part at all at any time in looking after the eggs, 

 as some authors have supposed them to do. They lay indolent and quiet 

 at the back of the tank for some days. On the 2nd April, one of them 

 began to swim about and come to the surface. She took not the least 

 notice of the eggs or of the males, nor the males of her. Even when she 

 came so close to the eggs as to brush them with her fins, the male merely 

 looked at her, or moved a little aside to let her pass. 



On the 5th April, a second deposit of eggs, comparatively small in 

 quantity, was observed, laid over the top of one of the other clumps. It 

 had been deposited during the night by one of the females. Three of the 

 usual dimples or cup-like depressions were noticed on the surface of them, 

 caused no doubt by the fondling snout of the male. 



On the 15th April, attempts were again made to induce the sentinel 

 male to eat mussels. He took no notice of those dropped at some dis- 

 tance ; if they came near, or fell on the eggs, he seized them, swam a foot 

 or two away, and ejected them. Very different was one of the females, 

 who devoured them in great numbers, as did also the other male, if within 

 what may be called his safety-zone, all his actions being dominated by 

 fear of the guarding male. The second female, perhaps the one which 

 had recently deposited the eggs referred to, still lay quiescent at the back 

 of the tank, and did not attempt to seize mussels. The active female 

 showed the greatest indifference to the lobster, and when by accident she 

 touched his open claws he merely withdrew a little further into his hole. 



From the first, the guarding male was observed to fan gently the mass 

 of eggs with his breast fins, clearly for the aeration of the eggs, but for 

 some time the action was leisurely performed and was by no means so 

 striking as it became later. It is certain that the duties of the male is 

 not confined to guarding the spawn from foes, but that an important part 

 of them include the aeration of the eggs by creating currents through the 

 mass, and the keeping of them clean. It is indeed a little surprising how 

 a sufficient supply of oxygenated water can reach the interior of the compact 

 mass by the narrow and tortuous channels v/hich exist between the adhering 

 eggs. The mass may be six or seven or more inches in diameter. It is 

 probable that under natural circumstances the surging movement of the 

 tides is the most influential agent in effecting this. At all events, from 

 the early part of April onwards, the male lumpsucker kept fanning the 

 spawn with more zest than at first. And on the 10th April another 

 action was for the first time observed. Placing his mouth about an inch 

 or so from the spawn he spouted water out upon it, the action of the 

 gill-apparatus being thus reversed, as I have observed also in plaice with 

 their snout above the level of the water.* 



* Twenty-second Annual Report, Part III., p. 287. 



