272 



which exist in Australia, Tasmania, and New Zealand, and 

 of which I possess a very large collection. 



Text-fig. 2. 



Dinotoperla carpenteri, n. sp. Tracheation of wings of last larval 



instar (x48). For lettering, see text-fig. 3, except cu-a, cubito- 



anal, and sc-r ; subcosto-radial trunk trachea. 



Text-fig. 2 shows the tracheation of the wings in the last 

 larval instar of the Hornsby species, Dinotoperla car pent eri, 

 n. sp. By comparing this with the imaginal wing-venation, 

 shown in text-fig. 3, the manner of fusion of M 3 + 4 with 

 •Cuj will be clearly seen. In the larval wing, trachea M 3 + 4 

 comes off obliquely downwards from the main stem of M, 

 runs alongside trachea Cu x for a short distance, and then 

 diverges from it again, running freely to the wing margin. 

 In the imaginal hindwing, the free basal piece of M 3 + 4 takes 

 on the appearance of a cross-vein descending on to Cu x at 

 right angles, and, consequently, the free distal portion of 

 M 3 + 4 , after its fusion with Cu x , appears as if it were a 

 true branch of this latter vein. It would, indeed, be 

 impossible to guess the true condition of these veins without a 

 reference to the precedent tracheation of the larval wing. 



The only other genera of Leptoperlidae, so far described 

 from Australia and Tasmania, are Leptoperla, Newm., and 



