NATURAL HISTORY SOCIETY OF GLASGOW. 231 



with high cloudy; the sea outside was calm and had been so for 

 some days; the air from the north was keen, but within the loch it 

 was much milder. Nothing special was noticed in the water that 

 evening. Next morning, July 17th, the sea was swarming with 

 Medusae. It was a gray, hazy morning; mild, with no sun, and 

 quite calm. Large Medusa aurita were progressing in all direc- 

 tions; Cydippe pileus, and Alcynoes were in immense numbers; 

 with Thaumantias and Sarzia pretty abundant also. 



We use a small towing-net, with a bottle attached, as a dipping- 

 net to pick up passing Medusae, and also allow it to hang below the 

 surface for the chance of any animal going into it. This morning 

 it was put down between half-past seven and eight o'clock, and on 

 drawing it up a number of little blackish creatures were observed 

 swimming merrily in the bottle, like a lot of small water -beetles. 

 When we got it on board, we saw at once that they were Pteropods. 

 The net was soon below the surface again, and this was repeated 

 with the same result again and again. In fact, the sea was 

 swarming with these Pteropods, so much so that the surface, as 

 they came up and touched it, was covered with little rings, like 

 those produced by gently-falling rain- drops, or as if some incipient 

 ebullition was taking place. They were quite visible to the naked 

 eye (especially against the light-coloured paint of the side of the 

 yacht), as they approached the surface, and then dropped down 

 again — for they appeared to be perpetually rising and falling, 

 swimming up and dropping down, but not swimming along the 

 surface. If the net was allowed to hang down a little while, the 

 bottle, when taken up, contained a deposit of Pteropods at the 

 bottom, and a number of them swimming among the Cydipp>es, 

 which were nearly as plentiful. The species was Spiricdis retro- 

 versus, Fleming. 



A few were transferred to a large bottle, where they had plenty 

 of free room and oxygen, and they survived till next day. The 

 others were speedily suffocated from their own numbers, perhaps 

 assisted by the Cydipp>es among them. A good many Chetochilus 

 septentrionalis were among them, and a few Zoeas of the shore crab 

 {Carcinus moeaas)hi the second or megalopa stage, in which the tail is 

 still free. We examined the Pteropods repeatedly daring the day — 

 the little creatures swam rapidly to the surface, rising with a peculiar 

 fluttering motion, perpendicularly or at an angle, and having reached 

 it, they raised the wings, as it were, above their heads, and holding 



