PUxtyciicuiis. 239 



Pallas' description. 



Forma et inagjiitudo Libell.t Puelhe. Thorax fasciatus, 

 ut in eadem. Caput fascia et striga transversa inter 

 oculos ; ceteroquin corpus albissimum, levissime rubicundo 

 vel ccerulescente varians. Abdomen subtus linea longi- 

 tudinali atra, quibusdam triplicata ; accedente etiam 

 dorsali, magis minusve interrupta. Pedum femora 

 bilineata, utrinque ciliata ; tibiiv dilatatai, ciliisque sub- 

 pennatai, albs, rhachi lineari nigra. Ahe hyalina:^, areola 

 versus apicem fusco-lutescente. (P. S. Pallas, " Reisen 

 durch verschiedene Provinzen des Riissischen Rciches in 

 den Jahren, 1768-74," vol. i., p. 469, 1771-76.J 



Size. 



Length of Male, 36mm. to 37mm. ; expanse of wings 

 43mm. to 46mm. Length of P'emale, 36mm. to 38'5mm. ; 

 expanse of wings, 45mm. to 48mm. 



Male Imago. 



Head, face blue, but labrum and labium }-ellowish ; 

 top of frons and of head black, with a blue interrupted 

 line across the latter in the region of the front ocellus ; 

 occiput greenish-blue. Eyes blue. Prothorax greenish 

 below, black above with greenish lines. Rest of thorax 

 pale green below ; above black with two longitudinal 

 green lines on each side ; projections at the attachment 

 of the wings and between them bluish-green. Legs 

 whitish-blue, with a dark line along the upper surface ; 

 tibiae much dilated and fringed with black hairs. Wings 

 hyaline. Pterostigma small, brown. Abdomen pale blue, 

 spotted with black, and with black sutures between the 



