DIPLAX. 179 



9. D. scotica! 



Libellula scotica Donovan ; Selys ! Revue des Odonat. 48, 22 (with the 

 synonyms). 



Fusco-olivaceous ; labium yellow, with a middle black band ; 

 labrum yellow, margined with black ; front yellow, a band anteri- 

 orly, obsolete or absent with the female, and another before the 

 eyes, black ; dorsum of the thorax olivaceous, the middle sulcus 

 broadly, triangularly black; dorsum of the male sometimes fuscous, 

 the middle black, with two yellowish spots each side; sides yellow, 

 with a broad, oblique black band; beneath black, with three cord- 

 iform, yellow spots ; feet black ; abdomen short, triquetral, black, 

 each side with a yellow, maculose stripe ; dorsum of the abdomen 

 entirely fulvous in the females ; appendages black ; vulvar lamina 

 triangular, erect, excavated ; wings hyaline, posterior ones of the 

 females flavescent at the extreme base ; pterostigma quadrangular, 

 black; membranule whitish. 



Adult Male. Mouth, and the front almost entirely, black; thorax 

 and abdomen black, with the yellowish marks absent, or almost 

 absent. Seven antecubitals; 5 T postcubitals ; three discoidal 

 areolets. 



Length 33 millim. Alar expanse 52 millim. Pterostigma 2 

 millim. 



Hab. North Red River (Robt. Kennicott) ; almost everywhere 

 in Europe ; Asia ; Wilui River, Irkoutsk, Siberia. 



The American specimens are hardly distinct ; but the color is a 

 little different ; the black labial stripe is narrow anteriorly, trian- 

 gular; the dorsum of the thorax is of an olive fuscous color, trans- 

 versely interrupted, so as to appear 4-spotted ; dorsal middle of 

 the abdomen, in- the female, somewhat black. 



10. D. intacta ! 



Diplax intacta Hagen ! 



Fuscous; mouth and front white ; labium in the middle (9) 

 black, and in adult male, all black ; front with a black band before 

 the eyes; vertex black, with a pale spot above, or all black (adult); 

 thorax nigro-fuscous, dorsum each side with an obsolete fulvous 

 stripe, sides fuscous, obsoletely varied with black; the adult male 

 has the thorax brassy-black; feet black; abdomen short, somewhat 

 broader before the apex, fuscous, with dorsal, phalerate, fulvous 

 spots ; upon the base and segments 6 t they are larger ; or black, 



