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 eges with his breast fins, clearly for the aération 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 aération of the eggs by creating currents through the 
mass, and the keeping of them clean. It is indeed a little surprising how 
a sufticient supply of oxygenated water can reach the interior of the compact 
mass by the narrow and tortuous channels which 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, 
