1907. Notes, 323 



ZOOLOGY. 



A Note on Leptoplana tremellaris. 



As the feeding habits of this interesting species, the common Film- 

 Worm or Living Film of our coasts, have, perhaps, not been very closely 

 studied, the following observation may be worthy of record. On the 

 morning of the 10th July last, I placed in a dish of sea-water, with several 

 living specimens of Leptoplana, gathered on the rocks of Red Island, 

 Skerries, some days earlier, a single living specimen, nearly one inch 

 long, of the small Razor- fish, Solen pellncidus, dredged off Skerries harbour 

 the previous evening. Leaving the Solen in the apparently harmless 

 companionship of the Film-worm, I went away, and returned some 

 hours later with the intention of observing the motions of the Razor-fish, 

 which had been particularly lively when placed in the dish. To my 

 astonishment, I found the. valves of the Solen lying wide open, inner side 

 upwards, with the Film-worm sprawled across them, and in the act of 

 gliding away with its peculiarly even motion. When the worm had fully 

 passed off the valves of the Solen I found them quite empty. Not a trace 

 of the living Razor-fish was to be seen, and the swollen state and dark 

 colour of the central region of the worm, originally almost as film-like 

 and pellucid as the rest of its body, showed that it had just gorged itself 

 on the unfortunate Solen. The broad elliptic-shaped worm, to all 

 appearance a mere slice of plastic jelly destitute of any definite organs or 

 weapons of defence, had, no doubt, extended itself to a narrow ribbon, and 

 then, sliding in through the slightly gaping end of the Solen valves, had 

 proceeded to devour the living tenant. The process by which the Living 

 Film absorbed a Razor-fish fully as large as itself must be one of suction. 

 Perhaps some reader of this journal who has studied the habits of 

 Leptoplana tremellaris can tell us something about its feeding mechanism. 



N. CO^GAN 



Saudycove, Co. Dublin. 



Scarcity of Wasps. 



One of the most noticeable events here in insect life this summer is 

 the total absence of wasps. A few queens (now all disappeared; but not 

 a single worker. Has the cold weather in June and early July annihilated 

 every species of wasp in Ireland, or is their absence here merely a local 

 characteristic ? 



R. M. Barrington. 

 Fassaroe, Bray. 



