NOTES ON BRITISH ODONATA IN 1921. 125 



NOTES ON BEITISH ODONATA IN 1921. 



By W, J. Lucas, B.A., F.E.S. 



My first dragonfly experience for 1921 was the receipt of a 

 very teneral male Pyrrhosoma nymphula, Sulz., from G. T. Lyle, 

 which he captured on 1 May at Wicken Fen. I did not myself 

 meet with a dragonfly till 16 May, when Ischnura elegans, 

 Vanderl., was found in large numbers — many mature, a smaller 

 number teneral — along a ditch or drain at Lodmoor, Weymouth. 

 On 18 May I took in the New Forest a male P. nymphula, 

 fairly mature but still with the thoracic markings yellow instead 

 •of crimson. The next day, in addition, I met with Calopteryx 

 virgo, Linn., Libellula depressa, Linn., and Gomphus vulgatissimus, 

 Linn., most, if not all, of which appeared to be teneral. On the 

 20th Libellula quadrimaculata, Linn., was captured in somewhat 

 teneral condition and Orthetrum caerulesceiis, Fabr., decidedly in 

 that state ; Agrion puella, Linn., male, was, however, taken 

 mature, and P. nymphula, which was by then common, was 

 secured with crimson thoracic markings for the first time. On 

 '21 May Cordnleg aster annulatus, Latr., was met with, and by 

 this time the dragonfly season may be said to have been in full 

 swing. 



.ffiscrmidse. 



Gomphus vulgatissimus, Linn. Besides the one seen on 

 19 May, a pair were taken in copula on 7 June near Oberwater 

 in the New Forest, and the species was seen again in the same 

 locality on 9 June. 



Cordulegaster annulatus, Latr., was first met with in the 

 New Forest on 21 May, and last noticed in the same place 

 between 31 Aug. and 20 Sept., when dragonflies, no doubt owing 

 to the drought, were no longer common in the Forest. 



Brachytron pratense, Mull. On 6 June two males were taken 

 at Marlborough Deeps in the New Forest. 



Aeschna grandis, Linn., was seen ovipositing in the Long 

 Water at Hampton Court, Middlesex, on 19 August. At the 

 Hut Ponds near Wisley, Surrey, it was seen on 22 Aug. 



Ae. cyanea, Mull. On 5 Sept. a male was caught near 

 Avonwater in the New Forest. While held by its wings a fly 

 was offered it about the size of a house-fly— one of those that 

 follow one so persistently in the summer. This it took readily 

 ■and ate; but a second that was offered was refused. ^Wlnle its 

 wings were held it was still able to set up vibrations in some 

 wa\\ Its head and surrounding parts were seen to be in motion, 

 so it seemed clear that these vibrations were not due to move- 

 ments originating in the wings. The last dragonfly seen during 

 the season was an Aeschna (orobably of this species), flying 

 •about a Scotch Fir at Oxshott Heath, Surrey, on 29 October. 



