44 THE CANADIAN ENTOMOLOGIST. 



situation, some pupating on the bottom of the box, others beneath the 

 lid, while others again attached themselves to the side, in every instance 

 producing a perfect beetle. The lot of larvae taken August 24th had all 

 changed to pupa on September 8th. They began to emerge on September 

 17th, and were all out on September 20th. 



On August 26th, I found a large colony of larvae and beetles. The 

 larvae were of two sizes, some very small and others about full grown, but 

 about the only noticeable difference, apart from size, was that in the young 

 larvae the yellow markings were scarcely to be seen. The small larvae had 

 lately moulted, and the cast skins were on the leaves, showing that in this 

 respect Physojiota differs from Coptocycla and Cassida, the larvae of 

 which slip the cast skins on the tail. Until nearly full grown, the larvae 

 of Physonota are social, keeping together in compact groups, the heads 

 in the centre, surrounded by a circle of uplifted tails, presenting a most 

 curious appearance. When nearly full grown they separate and scatter 

 over the plants. By most of the later writers on the insects in question, 

 but one species is recognized, P. iinipunctata Say. Prof Riley, in the 

 Supplement and Index to Missouri Reports, p. 53, says : " Physonota 

 qiiinquepicnctata Walsh & Riley (Rep. ii., p. 59). — This is synonymous 

 with Ph. jmipunctata (Say), there being no question as to the specific 

 identity of the two, both having been bred by Mr. F. H. Chittenden, of 

 Ithaca, N. Y., from larvae on wild sunflower (Helianthus)." That P. 

 quifiquepunctatay^ . & R. is synonymous with T'. helia?ithi Rand., is I 

 believe correct, but its identity with P. unipunctata Say is I think still an 

 open question. With regard to this point Dr. Hamilton writes me : " But 

 even if they were so bred, it does not prove identity, because (if species) 

 both are found in the same vicinity, and may have mingled on the same 

 plant. Besides it may have been heUanthi instead of utiipunctata., since 

 both go by the same name." 



The records of these species appear to me to point to the conclusion 

 that they are distinct. Say describes his species as yellow, with the margin 

 whitish. Dr. Hamilton, Can. Ent., vol. xvi., p. 135, speaking of a colony 

 of unipunctata found by him, states that all taken were of Say's type, pale 

 above with one black spot on thorax. He also tells us that a few of the 

 larvae were feeding with them, their colors bright yellow. As in all the 

 CassidcB the colors change after death, I wrote to Dr. Hamilton, asking 

 him what the color of the specimens found by him was in life. In answer 

 he informed me that all taken by him were entirely pale, except the black 



