THE RESPIRATORY ORGANS OE A NOToNliCTlD. 



B\- Stki'uen (tOttiieil Rich. M.A. 



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In the Annals of the luitomolos^ical S(X'iety of .\nierica for 

 December, lyi^), Mr. ]. R. de la Torre Bueno has imblished an 

 interestincr article on the A<[uatic Heniiptera. In the course of 

 this article, Mr. Bneno says: 



riu-ro arc tlirrc main iiums of respiratory apparatus among llic water- 

 (hvellcrs. which may he called the dorsal reservoir and pile, the anal lube, 

 and the abdontiual ehannel types. The tracheal systems as such are prac- 

 tically identical in all three forms of air supply. The CorixidcT. Belosto- 

 mida\ and .X'aucorid.e ha\e '.he dorsal reservoir: the Xotonectidre the 

 ahdnniiun! channel; and tlic Xepid;e the tnhe type. 



He g'oes on to describe the three types in detail. 



The rather meagre description which Mr. Buen<:» gives of 

 the abdominal channel type of air supply, found in the Notonec- 

 t'ulx, suggested t<:) me that it might l)e well to undertake the study 

 of this feature. In the .\manzimtoti River, Natal, I was able 

 to secure a good sujjply of Notonectid material, which, how- 

 ever. I have thus far not been able to identify. 



Eigure i shows the ventral aspect of the abdomen of my 

 material. Mr. Bueno's description, which I (|uote in full, will 

 here apply : 



It (the abdominal chaimel ) is, however, extremely simple. The 

 abdomen is keeled down the middle, and from this keel spring outwardly 

 towards the sides of the body elastic ;md fairly stiff .ind close-.yrowinp: long 



