Xotes on the Cases of some South Brazilian Trichoptera. 



end of the boring a small hole is gnawed through the wall of the stick for the 

 issue of the respiratory current. For its transformation the larva fixes the ventral 

 side of the mouth-end of its case to some stone or tree (preferring the latter, 

 when obtainable), and closes the entrance with a stone; the interior of the stick is 

 clothed with a silken tissue, forming a cylindrical cocoon, closed with a sieve at either 

 end; the centre of the anterior sieve is attached to the stone, which serves as a 

 covering. It often happens that the larvae find hollow sticks; but even then they 

 gnaw, before their change, a quite purposeless hole through the wall of the stick. 

 (See Kosmos, "Gratulationsheft zum yojahrigen Geburtstage Ch. Darwins". p. 395, 

 fig. 6.) l ) The pupae agree in the number and arrangement of the corneous patches 

 of the abdomen with those of Helicopsyche, but each patch is armed with from 

 four to six sharp hooks. The branchiae of the pupa are not shed in the final 

 transformation ; they can easily be seen in the imago when it is put into spirits 

 of wine immediately after issuing from the pupa. 



Sometimes tubes of Grumicha are met with, which, instead of a corneous 

 covering, are shut with a stone (such were, e. g., the tubes described by Hagen 

 in Stettin, entom. Zeit. 1864, p. 226), and these, on examination, are found to con- 

 tain pupae, not of the maker of the tube, but of an intruding Tetracentron. I 

 do not know whether it is a distinct species. 



In some small mountain rivulets I have found tubes of various smaller Lepto- 

 ceridcp. (Setodes (?), Grumichella, c.) tenanted by intruders, which have the curious 

 habit of fastening to the mouth-end of the tube bits of wood or sticks, sometimes 

 much longer than the tube, and concealing it almost completely. I have not yet 

 seen the imago, but the larvae agree (e. g., in the two-jointed tibiae of the hind 

 legs) with those inhabiting hollow sticks. 



Genus II. Grumichella, nov. gen. 



(Very nearly related to Leptocerus. The neuration of the anterior wings is 

 quite the same; in the posterior wings apical fork No. i is wanting, while 

 Nos. 3 and 5 are present in both sexes. Proportion of the joints of the 

 maxillary palpi 10, 15, 20, 9, 17.) 



The larvae inhabit waterfalls and rapids of mountain rivulets. But for size 

 their tubes closely resemble those of Grumicha, which are thrice as long. It is 

 rather curious that those almost identical tubes should belong to species quite 

 different in their larval, pupal and imago states. 



The tubes of Grumichella show two interesting contrivances, by which they 

 are adapted to their peculiar habitat i, from the wall which closes the tail-end 

 of the tube, and which has, as in Grumicha, a central circular opening, there 

 projects, on the ventral side of the opening, a short, stout, triangular tooth or 

 spur, which, being inserted into minute crevices of the rocks, probably serves to 

 give hold to the tubes; 2, the little petiole or foot-stalk of the disc, by which the 

 pupa case is fastened, does not proceed, as in Grumicha, from the margin of the 

 tube, but from the corneous covering. The pupa cases being usually fastened 

 with the mouth-end turned upwards to perpendicular rocks, along which a thin 

 sheet of water is pouring down, if the; tubes were fastened, the pupa 1 , after having 



i) = - Ges. Schriften S- 685. 



