170 Mr. R. McLachlan on new 



y 



I have examined six males of G. scintillatts, collected 

 by Mr. Bates at St. Paulo, on the Upper Amazons. The 

 female, probably, has the base of the posterior wings 

 hyaline, as in rutiJans. 



The almost total suppression of red markings on the 

 body, the short pterostigma, and the difference in the 

 coloration of the posterior wings, both above and beneath, 

 establish this as a good and distinct species. Besides, 

 Mr. Bates informs me, that he found C. rutilans only at 

 Para,* and C. scintillans only at St. Paulo, the distance 

 between these places being 20° of longitude, or 1800 

 miles by the river. 



Fam. GOMPHID^. 



I propose to describe here an insect pertaining to the 

 genus Tetalia, of Hagen, in its broad sense, the species 

 of which are still most rare in collections. De Selys 

 (Mon. Gomph.) divides Petalia into two sub-genera, 

 Petalia and rhyllopetalki, formed on certain differences 

 in neuration and markings; these latter are, in all the 

 three described species, of a nature almost unique in 

 the Odonata, and the insects possess general characters so 

 very remai^kable, that one is almost inclined to doubt 

 whether it would not be better to consider all the species 

 as members of one genus, varying specifically in minor 

 details. My insect will not fit itself into either of the 

 two divisions, and, following the authors of the *' Mono- 

 graphic," I have constituted a third for its reception, 

 under the term 



Hypopetalia. 



It differs from Petalia and PhyUopctalia in having 

 three cellules in the discoidal triangles of all the wings, 

 instead of two only, and the internal triangles have three 

 cellules in the anterior ^vings and two in the posterior, 

 (see wood-cut ; a, anterior, h, posterior wing) whereas in 

 the other divisions these triangles are alto- 

 gether free in all the wings ; furthermore, 

 there are five cellules in the anal triangle of 

 the postei'ior -wings ; the space surmounting 

 ^[^XT/^ 7 the triangles is divided by a nervule in all the 

 ^^ wings. The nodal sector is waved, as in 



* M. (le Selys Longcharaps recorded ("Secondes additions auxCalopt.") 

 C. rutilans from Sautarem, as be now thinks in error. Mr. Bates has no 

 recollection of havuig found either form between ParS. and St. Panlo. 



