284 British Dj'agonflies. 



puncto marginali atro. Corpus supra . viridi-caeruleum, 

 nitidum, absque ulla alia mixtura ; magnitudo pr^eceden- 

 tium duarum. . . . (S). Libellula corpore ca^ruleo 

 cinereoque alterno ; alls puncto marginali nigro. Dp:s('R. 

 Al(E albse, puncto marginali atro. Abdot)iiiiis articuli a 

 tergo visi antice cinerei, postice cxrulescenti-nitidi ; ante- 

 penultimus et ultimus articulus in plerisque cinereus, 

 nullo modo nitidus. (C. Linnaeus, " Fauna Suecica," ed. ii., 

 PP- 2>7S-}>7^, n- 147 1- 1 76 1.) 



[(rt) appears to be ^. puella, female. (;3) is, no doubt, Pyrrhosoma 

 nvmphiila. (y). The identity of tiiis insect does not seem clear. 

 (5) appears to be Eiiallagma cyathigerum or A . pitcUn, male.] 



Male Imago. 



Face bluish ; a black line at base of labrum, and another 

 at base of nasus. Top of head black-bronze, with a comma- 

 shaped blue spot behind each eye ; under-surface of head 

 blue. Prothorax black-bronze, three-lobed, but not 

 deeply cut or much raised, middle division lightly 

 notched in centre, edged all round with blue. Thorax, 

 dorsal surface black-bronze, with two entire, blue, 

 longitudinal stripes ; sides and lower surface blue, pro- 

 jections between wings blue. JVings hyaline ; pterostigma 

 black, centre surrounded by pale ring, and bounded 

 by stout nervures. Tegs black above, bluish below. 

 Abdomen blue and bronze-black ; segment i, blue, with 

 somewhat semicircular basal black spot ; 2, blue, with 

 U-shaped spot not reaching the circlet behind it 

 (Plate XXVI.) ; 3 to 5 blue, with distal quarter black ; 6, 

 blue, with distal half black ; 7, all except narrow basal 

 ring black ; 8, blue, with two tiny black spots ; 9, blue, 

 with distal three-pointed black spot ; 10, black, with 



