JULY 159 



about as much as one thousand sticklebacks ; but the 

 strangest part of Persson's narrative still remained to 

 be proved namely, that the lumpsucker ' blew on the 

 roe.' Proved it was most conclusively. 



' 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. . . . From the early part of April onwards he 

 kept fanning the spawn with more zest than at first ; and on 

 April 10th 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 current created was so 

 strong as to sway the algae growing on the side of the tank, 

 as well as the tentacles of an anemone in the neighbourhood, 

 and even to cause the whole mass of eggs to rock visibly 

 backwards and forwards. This action was done at brief 

 intervals, and from this time onwards. Later, when the 

 eggs were hatching, it was redoubled, and great activity was 

 shown with the fins. The movement thus created in the 

 water very probably helped the escape of the larval fishes 

 from the eggs. At this time the pumping or blowing action 

 was at the rate of fifteen or sixteen in ten seconds, and in 

 the pauses the fins were kept vigorously at work.' 



Whence it appears that hatching out lumpsucker 

 eggs is not the simple matter it might be deemed. 

 Professor M'Intosh, indeed, ascertained this several 

 years ago by repeated experiments, which always ended 

 in putrefaction of the whole mass ; and it is now clear 

 that, to keep the eggs alive, it is necessary to force 

 oxygenated water into the interstices between the eggs, 

 and that the male parent understands the increasing 

 urgency for this during the later stages of incubation. 



