226 PROCEEDINGS OF THE CANADIAN INSTITUTE. 



THE CRUEL Vl.A^T—( PHYSIANTHUS ALBENS). 



BY Arthur Hakvey. 



I find that a specimen of this phvnt was exhibited to the Linnfean 

 Society in 1867-68, to show the seed-vessel, and this is the only- 

 reference to it I have seen in Scientific Societies' proceedings. It is 

 a, little curious that both Mr. Charles Armstrong and myself should 

 have independently of each other prepared a paper about it for the 

 Canadian Institute. Mr. Armstrong's note, read before our Biologi- 

 cal Section, dealt with the genus Asclepias of which it is a mem- 

 ber ; I shall not repeat his statements, but at once draw atten- 

 tion to the Physimithus albens, of which I have a specimen for your 

 inspection. The plant I have is two years old ; it is a climber which 

 covers a trellis about four feet square. I kee|) it in a cellar in winter, 

 and set it in the open air in the end of May. It begins to flower in 

 August, and no sooner do the flowers open than moths, attracted by 

 the perfume, (which is not unlike that of the hyacinth, but not so 

 strong) visit the plant and find that excursion their last. The speci- 

 men before you shows a moth caught in the trap by its proboscis, and 

 you can see dozens of them in the same xinfoi'tunate " fix " through- 

 out the flowering season. This moth is the "Silver Y" {Noctia 

 gamvia), and by far the greater number of moths caught are 

 of this kind. I have, however, noticed an occasional cabbage 

 butterfly (pieris rapce) and a few wild bees and ants — the latter 

 caught by the leg. We will now investigate (1) the machinery which 

 catches the moths, and (2) the raison d'etre of the trap. 



The Physianthus (bladder Hower) is named from the shape of the 

 corolla, which swells near the base into a sort of bulb, enclosing the 

 following machinery — two ovaries and a pistil, covered by a sort 

 of cap which fits upon them, around which are five eyes, from which 

 points five pairs of recurved jaws extend. Under these jaws are 

 two anthers, closely pressed between the jaws and the seed-vessel. 



