370 Mr. E. M'Lachlan on Odonata fro?n 



2 in the triangle ; post-trigonal cellules commencing singly, 

 then two rows, followed by three, and increasing ; subnodal 

 sector furcating on a level with the pterostigma (slightly 

 before in the posterior) ; posterior wings with 12 ante- and 

 postnodal nervules ; 2 supra-trigonal and 2 in the principal 

 triangle ; anal triangle with 3 cellules. 



Length of abdomen (cum append.) 54 millim. ; length of 

 posterior wing 48 millim. 



Moupin, one male. 



It is probable that the nearest ally of this well-marked 

 species is the Japanese yE". vielanictera, Selys, which it 

 resembles in the possession of the strong tooth on the tenth 

 segment, and there is some amount of affinity in the structure 

 of the apex of the superior appendages ; but the small 

 size, very small pterostigma, much shorter appendages &c. 

 of the present insect are opposed to any very close rela- 

 tionship. The remarkable bird's-head-like profile of the end 

 of the superior appendages is reproduced to some extent in 

 the European JE. cyanea and the North-American M. con- 

 stricta, but neither of these has the tooth on the tenth 

 segment. 



N.B. — The female from Ta-chien-lu referred doubtfully to 

 2E. juncea in my former paper has no relationship to the 

 present species, and was probably correctly referred. 



Subfam. Caloptemygina. 



Calopteryx Oberthiiri, M'Lach. 



One female is from Siao-Lou, in the same district as Ta- 

 chien-lu. 



Matrona basilaris, Selys. 



Nearly thirty examples of both sexes from Siao-Lou, Mo- 

 si-mien, Moupin, and other places in the district, all pertain 

 to the type form and not to the race m'gripectus, Selys. 



ArcMneura incarnata, Karsch. 



One adult female from Siao-Lou. As this sex has not 

 been described, I append a description, omitting points common 

 to both sexes : — 



$ . Labium pale yellow, with a narrow black border and a 

 black line at the base, emitting a central prolongation not 

 extending across. Colour of the body brighter green ; a 





