144 Dr. Fritz Miillcr's Notes, ^-c. 



in an upright position. The case of the pupa is some- 

 what compressed, oval or ckib-shaped, rounded at the 

 upper, attenuated at the lower, end. The pupa emerges, 

 for its final transformation, at the upper end of the case. 



Genus VI. Peltopsyciie. 



The larvns live in larger tributaries of the Itajahy, pre- 

 ferring rapids. One species (/^. Maclachlani) has as yet 

 been found only in one single rapid near the mouth of the 

 AVarnow. The cases resemble in shape, colour and size 

 the well-known egg-cases of Nephclis, and are fixed, often 

 in very large numbers, to the upper side of stones ; they 

 are made of a brown, rather tough, coriaceous substance. 

 Their upper wall forms a rather flat elliptical shield, 

 smooth in P. Maclachlani, tra.nsversely striated in 

 P. Sieholdii ; the basal Avail is very thin, and firmly 

 glued to the underlying stone, so that it can hardly be 

 sej)arated without being torn. At either end of the case 

 there is a small circular opening. In most Hi/droptilid(B 

 the abdomen of the older larva? is much swollen ; in 

 Pelto]}syche it is so in a quite extraordinary degree, 

 filling nearly the whole case. The very slender anterior 

 part of the body is bent and hidden beneath the huge 

 abdomen, of which it appears to be only an insignificant 

 appendage. The pupa3 are remarkable for the unusually 

 great difference Avhich the complicated corneous patches 

 on the back of the abdomen show in the two species. 

 The perfect insects differ from all known Trichoptera by 

 the antenna? of the $ , some of the basal joints of which 

 are produced into long processes exhibiting a complicated 

 structure, very different in the two species, and which 

 J have not yet been able to unravel in a satisfactory 

 manner. From what I have seen, I am led to suppose 

 that these strangely modified basal joints of the antennae 

 may be odoriferous organs. 



