DESCEIPTIONS OF AUSTEALIAN ^SCHNIN^. 6 



larvse which I have examined. Needham, however, after noting the fact, is 

 content to allow the notation o£ the imaginal venation to remain in such a 

 state that the true origin of the so-called anal vein of the imaginal wing is 

 obscured. In my studies on the anal trachea of Anisoptera *, undertaken 

 mainly with the view of determining the phylogenetic development of the 

 anal loop, I was impressed with the great importance of a correct naming 

 for the veins that arise around the tracheae of this part of the wing. To make 

 the point quite clear, T give herewith figures of the tracheation of the wings 

 of a nearly full-grown larva of yEsclina hrevistyla, Ramb. (figs. 1 & 2). In 



Figs. 1 & 2. — Fore and liind wing-cases of nearly full-grown nymph of JEsclina brevistyla, 

 Ramb., to show tracheation. Permanent venation omitted, except for continuations 

 of A , Br, and sides of t. 



Tracheae : — A, anal ; A', A^, A.^, A.^, its branches ; Ac, anal crossing; arc, arculus ; 

 Br, bridge from Bs ; Brs, bridge from Bsjd ; Brs', bridge from Ms^jI ; Cu, cubitus ; 

 Cmi, Cu2, its branches; M, mediana ; M^, M.-,, M^, 3f^, its branches ; Mspl, median 

 supplement; iV, nodus; B, radius; B.^, its upper branch; Bs, radial sector; 

 Bspl, radial supplement ; Sc, subcosta. 



Spaces: — Al, anal loop ; At, anal triangle ; t, triangle. 



these, as in all Anisopterid nymphal wings examined by me, trachea A joins 

 trachea Cti very close to its origin, in the same manner that M joins i?. 

 Then Cu and A run along together as far as the future first cubito-anal 

 cross-vein. At this point, A bends sharply downvsards away from Cu. 



* The results of this study will shortly be published. 



