338 ENTOMOLOGICAL SOCIETY 



upon the adults. Captain Casey remarked upon the extreme con 

 trast in the large size of the larvae and the small size of the adults 

 in a number of the specimens exhibited, and there was some dis 

 cussion upon this phenomenon in other groups. Dr. Gill stated 

 that this disproportionate size of the larvae occurs markedly in the 

 Surinam frog as well as with the common eel and the Conger eel. 

 In fact, with all apodal fishes the difference is so striking that the 

 larvae in some cases have been referred to a different order from 

 the adult. Mr. Schwarz spoke of the same fact among the Cole- 

 optera, the only exceptions to the rule of the superior size of the 

 larvae being among the Carabidae, where all except the Harpa- 

 linae have the full-grown larvae apparently smaller than the adult. 

 This inferiority of size, however, is only apparent since the re 

 moval of the elytra of the adults shows in reality a smaller body. 

 The most remarkable cases of the greater size of the larvaa occur in 

 the Passalidae. Among the Phengodidae, what he takes to be the true 

 larva of the male of one species is very much larger than the adult. 

 Dr. Gill, in speaking of the extreme differentiation among the 

 larva? of Acronycta as contrasted with the similarity of appearance 

 among the adults, stated that this afforded an added proof to his 

 mind that the larval stage is a secondary condition and not a pri 

 mary one. Mr. Cook said that in his opinion nothing could be 

 plainer than the proof, all through the Insecta, that the larva is 

 an intercalated stage. As bearing upon this subject, Dr. Kenyon 

 spoke of the variation in the hatching point, in the course of de 

 velopment, showing that in Myriapods of different groups the 

 young may hatch at very different stages of development, some 

 having only three pairs of legs when hatched and adding others 

 in the course of growth, while others have five pairs, and still 

 others twelve pairs on hatching. 



Mr. Schwarz spoke of " Southern Arizona and its Insect 

 Fauna." He reviewed the topography of Arizona, indicating the 

 exact points at which satisfactory collections of insects have been 

 made. The most salient feature of the insect fauna of this region 

 is that the time of appearance or activity does not depend upon 

 the increase of temperature as in the more eastern portion of the 

 country, but is governed by the increase of humidity. By far the 

 greatest portion of the insects, and among them the most charac 

 teristic genera and species, do not make their appearance before 

 the beginning of the rainy season in July or August. 



