156 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



( 'areful and repeated examination of larvae of Hypera punctata 

 convinced me that no such tubercle exists. Furthermore, larvae 

 were observed at various stages in the process of constructing 

 their cocoons. It could be readily perceived that the thick irreg- 

 ular threads of viscous substance were drawn forth from the anus 

 by means of the mouth-parts, and there could be no doubt as to 

 the origin of at least the bulk of the material. Finally, dissec- 

 tions of Hypera larvae showed an enormous development of the 

 malpighian tubes; just what one could expect to find under the 

 circumstances. 



Ferris evidently could not afterward verify the presence of the 

 tubercle he had indicated in his earlier writings as the source of 

 the secretion. In his great work on the larvae of the Coleoptera, 1 

 which I have only recently had opportunity to examine, we not 

 only find no mention of the tubercle, but in connection with sev- 

 eral genera the positive statement that the secretion in question 

 issues from the anus. Under Hypera (p. 385) we find the follow- 

 ing: "They have the faculty of secreting from the anus a muci- 

 laginous and viscous substance which spreads over the body in a 

 very thin layer, principally over the ventral surface, and effec- 

 tively aids them in maintaining their position. This same sub- 

 stance, wholly insoluble in water, as it should be, also assists them 

 when they are about to transform to attach themselves to some 

 point, either upon the food-plant itself or to any other, and fi- 

 nally they employ it to surround themselves with an elegant irreg- 

 ularly reticulate cocoon constructed by drawing forth the muci- 

 lage in threads by the aid of their mandibles and palpi and the 

 movements of the body." 



A statement of the same import occurs under the genus Cwnu* 

 (p. 404-405): "They are habitually covered with a mucilaginous 

 substance which escapes from the anus and is spread over the body 

 by the peristaltic movements of the segments. At last the}' pro- 

 duce this substance in larger quantity, they allow it to harden, 

 and thus they find themselves enclosed in a parchment-like 

 cocoon which remains attached to the leaves, stalks or flowers." 



Ferris observed that even the internally feeding forms construct 

 their cocoons by the same process. Under Orchestes (p. 402), 

 whose larvae are leaf -miners, we read: "At the last the larva sur- 

 rounds itself with a cocoon which it forms with the aid of its mandi- 

 bles and palpi from a mucilaginous substance which issues from 

 the anus." 



J. A. Osborne, an English observer, makes a brief corroborative 

 statement. 'The spinneret of the larva of H. rnmicis is anal." 2 



1 Ferris, Edouard. Larves de Coleopteres. Paris, 1877. 



sborne, J. A. On the cocoons form,ed by Hypera rumicis and its 

 parasites, and Clonus scroprmla,ria\ Ent. Mo. Mag., vol. 16, p. 16-18, 



lo/ .7 . 



