( 131 ) 



IX. Notes on the Cases of some South Brazilian Tricliop- 

 tera. By Dr. FiiiTZ Mullek.* 



[Read May 7th, 1879.] 



Little is known about the cases of extra-European 

 Trichoptera. A short account of those observed by me 

 in Southern Brazil may therefore be of some interest. 



Of the seven families into which Trichoptera are at 

 j^resent divided, only five have as yet been found here, 

 Adz., SericostomatidcB, Leptoceridce, Hydropsy chidce, Rluja- 

 copliilidce and HydroptilidcR. These may be grouped into 

 two main divisions according as their pupas are active 

 or inactive. In the first group, comprising the Sericos- 

 tomatidce, Leptoceridce and Uydropsychidce, the case of 

 the pupa is provided with small openings at either end, 

 through which a continual current of water passes moving 

 from the anterior to the posterior extremity. The pupa 

 is in incessant activity to maintain this current ; this is 

 done, at least in most species, principally by the append- 

 ages at the end of the abdomen, which may be seen playing 

 in the opening at the hind-end of the case. In the second 

 group, containing the RhyacophilidcB and Hydroptilidoi, 

 the larva spins a cocoon clo^f'd all around, in which the 

 pvipa lies quite motionless. (This cocoon is either free 

 within the case (BhyacophilidcB), or confluent with the 

 walls of it (^Hydroptilidce). The fixity or mobility of the 

 cases does not afford a distinctive character of the two 

 last-named families; for there are not only Ilhyacophi- 

 lideous larva? living in portable cases and Ilydroptilidcous 

 larva3 living in fixed ones, but there are even cases fixed 

 and movable at the same time, being fastened by a long 

 flexible string (^Bhyacopsyche). 



* Figures and full descriptions of the cases mentioned in the following 

 notes have been sent for publication to the " Archivos do Muscu Nacional 

 do Kio de Janeiro." 



[Some additional notes appear in the Report of the Proceedings of the 

 Meeting of the Entomological Society, held on the 2nd April, 1S7U; (/. 

 Proceedings, pp. vi — viii. — Ed.] 



TRANS. ENT. SOC. 1879. — PART 11. (jULY.) 



