304 ENTOMOLOGICAL SOCIETY 



ing as matrix to the hairs ; the change in form of the oesophagus 

 which acts as a pump in sucking the blood ; the course of the 

 oesophagus through the brain ; the large epithelial cells of the in 

 testine ; the structure of the brain ; histology and topographical 

 anatomy of the muscles ; the differentiation of the glands of the 

 head into three distinct kinds ; the microscopical anatomy and 

 histology of the excretory and genital organs. 



Dr Gill read a paper entitled " The larva of insects an inter 

 calated stage," of which the following is a summary : 



THE LARVA OF INSECTS AN INTERCALATED STAGE. 



By THEODORE GILL, M. D., PH. D. 



{Author's Abstract.~\ 



The vermiform larval stage of insects, manifested' under the 

 form of caterpillars, grubs, or maggots, was regarded by the old 

 naturalists as a primitive condition and proof of the inferiority of 

 the worms in a systematic sequence. This view was especially 

 urged by one author who enjoyed a great popular reputation in 

 his day in a memoir which long had influence on American 

 entomology " The classification of insects from embryological 

 data," by Prof. Louis Agassiz, published in 1850. 



It was contended by the speaker that the specialized larval condi 

 tion, as the caterpillar or grub, was rather an intercalated stage. 

 The geological record especially seemed to indicate that such was 

 the case. The predominant insects of the paleozoic epoch were 

 representatives of orders without a vermiform stage or were evi 

 dently related to the representatives of such orders as the Ortho~ 

 ptera and Neurorthoptera. Data in support of this view compiled 

 from recent works by Mr. Scudder were furnished. 



The diversity of the larval stage among insects similar in their 

 imaginal stages was also adduced in evidence. 



APRIL 7TH, 1892. 



President Riley in the chair. Nineteen members and one visi 

 tor present. 



Mr. Geo. D. Bradford, of New York, was elected a correspond 

 ing member. 



