150 British Dragonflics. 



the base, the last four segments dilated ; bronze-green ; 

 segments i and 2 with an orange mid-dorsal streak, 

 segments 3 to 7 with a long mid-dorsal spot con- 

 stricted about the middle ; this spot gets smaller as 

 the segments proceed posteriori}' ; segments 8 and 9 

 are entirely bronze. 10 is raised micl-dorsally and there 

 yellow. Upper aiuxl appendages cylindrical, hair\', black, 

 turning outwards at the point, with a sharp spine on each 

 near the base below, pointing vertical))' downwards ; 

 lower appendage shorter, orange, bifid, with the black 

 tips turned up (Fig. 31). 



Female Imago. 



Colouring much the same as that of male, dorsal 

 spots more conspicuous, absent from segment 7. Abdomen 

 much compressed, but rather swollen at each extremity. 

 Wi)igs much clouded with saffron, especiall}' towards 

 the costal margin. Pterostiguia black, a little over 2mm. 

 long. Vulvar scale hollowed out into a groove, projecting 

 but little, simple, not notched at border, less prolonged 

 than with the other species. The two anal appendages 

 are as long as the last segment, nearl}- black, down}', 

 cylindrical, and pointed. The eleventh segment is 

 yellowish. 



Date. 



June and Jul}- are the months when' O. eurtisii should 

 be sought for ujion the wing. 



Distribution. 



On June 29, 1820, Mr. J. C. Dale discovered this 

 new ]5ritish Dragonfl}' on Parlc}' Heath in Hampshire, 

 and subsequentl}' found it at llurne in Dorsetshire as 



