On a trichopterous insect belonging to the family 

 Leptoceridae with branchiae 1 ). 



The Secretary exhibited a specimen, in alcohol, of a trichopterous insect, 

 showing tracheo-branchiee, sent from Brazil by Dr. Fritz Miiller, who communicated 

 the following note concerning it: - 



"I send you enclosed a trichopterous insect belonging to the family Lepto- 

 ceridce, which shows very distinctly the branchiae lately discovered in the imago 

 stage of this order by Dr. Palmen 2 ), of Helsingfors. As these branchiae cannot 

 be readily seen excepting immediately after transformation, I think many members 

 of the Entomological Society may not yet have seen them. I may add that 

 Dr. Palmen's view, that the branchiae persist in all those Trichoptera the larvse 

 and pupae of which possess them, does not hold good. At least in one species 

 of Leptoceridce I have observed that they are cast when the pupa undergoes its 

 final transformation." 



Mr. M'Lachlan said that the discovery by Dr. Palmen of branchiae in the 

 perfect insects of many Trichoptera was an extension of the observations originally 

 made by Newport 3 ), and after him by Gerstacker and others, as to the existence 

 of branchiae in the imagos of various Perlidce. Dr. Palmen appeared to be of 

 opinion that these persistent branchiae serve no functional purpose in Trichoptera, 

 and alludes to them more particularly as proving that the branchial system of 

 the larva and the stigmatic system of the imago have no genetic connection, since 

 in the imago branchiae and stigmata may exist side by side. Mr. M'Lachlan 

 further alluded to the existence of marked branchial filaments in the imago of 

 various other genera of European Trichoptera not especially alluded to by 

 Dr. Palmen, such as Diplectrona, Plectrocnemia and allies, Ptilocolopus, &c., 

 and thought they might yet be found to serve a functional (respiratory) purpose. 

 The insect sent by Dr. Fritz Miiller showed two or three branchial filaments on 

 each side of most of the abdominal segments. 



1) Trans. Ent. Soc. London 1879. Proc. p. XIII. XIV. 



2) 'Zur Morphologic des Tracheensystems', 1877- 



3) Ann. & Mag. Nat. Hist. 1844. Trans. Linn. Soc. xx. p. 425 (1851). 



