Pyrrliosouia. 255 



suffused with a yellow tinge. Pterostignux )'ello\v. The 

 dark markings are green-bronze rather than black-bronze. 



Variation. 



This species appears as a rule to vary very little. I 

 have, however, a female from which the median carina 

 of segments 2, 3, 4, 5 is abseiit, the swellings at its 

 base being represented b}- tin)- marks ; the spot on 

 segment 6 is reduced to a line with a distal swelling. 

 De Selys ("Revue," p. 179) describes a female from 

 Madrid in some respects the opposite of this. There is 

 a broad bronze band along all the segments, enlarged 

 towards the extremit\- of each : the yellow incisions 

 are well marked, and the usual crimson marking on 

 head and thorax are replaced by }'ellow. He adds that 

 Mr. Dale sent him from Dorset a similar variety. 



Oviposition. 



In July, 1898, on Esher Common, two or three pairs 

 were noticed flying, connected per collitiii, along a narrow 

 ditch draining into the large pond. Presently one of 

 these pairs went down to the water, and the female 

 rested on a floating leaf of Potamogetim, whilst the male 

 still held her, and remained with its body vertical and 

 wings horizontal (Fig. 2, p. 13;. The female then 

 moved the anal extremity of her abdomen about over 

 the leaf, as if she was ovipositing. /\fter two or three 

 minutes they flew away. The eggs could not at first 

 be found ; but when the leaf had withered, some little 

 ridges were noticed, and these contained bodies similar 

 to the eggs that had been extracted from the body of 

 a female. The eggs were laid within the substance of 



