11 



drawings of specimens and slides containing specimens mounted for microscopic examina- 

 tion. (This paper will appear separately in the 0. E.) 



Miss Cora H. Clarke exhibited a specimen of the work of some Caddis Fly larvae" 

 (Hy dropsy che), consisting of an aggregation of mud cells on a small stone, beyond which 

 were the nets spread by the larva?. They were always found in running water, and 

 always had an opening toward the current, probably to enable the larva to catch the food- 

 coming down the current. In reply to a question from Dr. Morris, Miss Clarke said the 

 nets were often solitary, but not unfrequently aggregations were found. Another species, 

 of Plectrocnemia, builds a vertical tube of mud, sometimes with a number of branches : a 

 specimen was exhibited. Dr. Hagen thinks it an undescribed form. Reference was 

 made to figures in a paper entitled " Description of two interesting houses made by Caddis 5 

 Fly Larva?, by Cora H. Clarke." The larva? living in running water were difficult to 

 raise. 



Mr. Mann remarked that apropos of raising larva? living in running water, Prof. 

 Barnard, of the Dept. of Agriculture, had contrived an arrangement with which he had 

 great success with larva? of that kind. It consists of a glass tube, the bottom closed by »- 

 porous cloth, the other end fastened to a faucet ; the water could be thus kept steadily 

 flowing with any desired rapidity. 



Dr. Morris exhibited a gall recently collected, the inclosed larva not bred, and asked 

 for information as to the probable producer. 



Mr. Mann said the subject of galls had puzzled him in his bibliographical work, 

 especially as to the proper method of indexing them. He had referred to them under the 

 head of systematic botany, but doubted his correctness. 



Dr. Morris asked what orders of insects contained gall producers. Mr. Osborn 

 thought about all oiders except Xeuroptera and Orthoptera. Mr. Smith said that at least 

 one American species of Apion is known as a true gall producer, and in Europe several 

 species are known to produce root galls. Mr. Osborn said that many plants, especially the 

 Rosacea, were much subject to galls, while others were rarely if ever so infested. He 

 thought them abnormal products so far as plants are concerned, and as rather belonging 

 to insect economy since they are caused by insects ; not only that, but insects were often 

 most readily distinguished by the form of the galls, and in the case of mites those of the 

 maple and ash were much alike, but produced very easily distinguishable galls. 



Dr. Hoy thought the galls were pathological appearances, and were rather diseases of 

 plants and should be classed as such. In descriptive botany they had no place, any more 

 than in a description of the lips cancer should be treated of. 



Mr. Mann stated he had also indexed them under pathological botany and under in 

 sects, but the chief difficulty had arisen through a descriptive paper treating galls from a 

 botanical standpoint. 



Dr. Morris said that he had seldom seen such a dearth of larva? of all kinds, and 

 butterflies were exceedingly scarce. 



Mr. Saunders thought there had been no unusual want of insects in Canada. Turnus 

 has been common, and so was cardui ; the .latter, indeed, had been extremely abundant 

 in Manitoba, where it had destroyed large quantities of thistles, and caused great alarm 

 on the part of farmers, who thought it would also attack their crops. Thecla niphon, 

 usually rather a rare form, was found in some abundance this season, and in the early part 

 of May quite a number of specimens were captured. 



Dr. Hoy said that as compared with previous seasons, cardui has appeared in immense 

 numbers, fifty for one. It had never previously to his knowledge attacked the hollyhock 

 or sunflower. This season it has literally stripped the leaves from these plants, preferring 

 them apparently to thistles. Other butterflies had been scarce. 



Prof. Osborn said in Iowa butterflies had been unusually common. 



Mr. Underwood said he had found butterflies unusually common in Central N. Y.. 

 turnus especially, but for five weeks spent in Connecticut everything was scarce excepting 

 cardui. 



Prof. Fernald said in the first part of the season insects were very rare. Butterflies 

 alone appeared about as common as usual, turnus unusually common ; cardui had been 

 rare until this summer, when it was common. Last season Mrs. Fernald had collected 



