— 24 — 



tioned by BROCHER, in his figured spécimen the wings reich 

 anidway on 5th segment ; this form I hâve had in a very great 

 number; in my material, the wings are varying in length, when 

 shortest reaching into Ist abdominal segment, when longest 

 reaching into 4th segment. The legs are a little longer than in 

 the typical form. The female colored like the typical form, 

 the maie unicoîorous, but of a paler brown. Length 0,5 — 0,8 mm. 



The second variety, var. solitaria RUSCHKA and ThIENEMANN, 

 has been mentioned by thèse two authors (as a separate species), 

 and by RlMSKY-KoRSAKOW (1), and also I hâve hat it in number. 

 The female differs from the typical form by having just as rudi- 

 mentary wings as the maie; it is a little more clumsy than the 

 typical form, especially the legs a little shorter and the head 

 a little broader. Also more scanty set with bristles. The colour 

 in both sexes paler brown with hind part of thorax, antennae 

 and legs pale. Length 0,4 — 0,7 mm. 



As it will be seen, neither the length of the wings nor the 

 colour are characters allcwing the maintenance of solitaria as 

 a species, it is only a variety just as brevipennis . 



Neither does the solitary occurrence in the host egg hold good 

 as a character, as var. brevipennis can parasitize singly (in 

 small eggs) and in numbers (in big eggs), the number of para- 

 sites thus appearing to dépend on the size of the host egg. 



As hosts for the typical form are recorded : by ENOCK (2), 

 Notonecta-, Dytiscus- and Colymbetes-eggs; by RlMSKY-KoRSA- 

 KOW (3), eggs of Dytiscus and smaller Dy.iscids in Alisma- and 

 Ca//a-stalks ; by HEYMONS (4), Ranatra linearis-eggs ; by 

 UssiNG (5), Aphelocheirus Montandoni-eggs. 



The number of individuals would amount to 50 in an egg. 

 This form I hâve reared from a Dytiscus-eggs in an ^4/isma-stalk, 

 in Hjorteso near Hillerod; the number of parasites was 9. 



Var. brevipennis I hâve reared from Agabus-eggs, in Ranun- 

 culus /r'ngua-stalk Funkedam at Hillerod (5 — 8 spécimens in 

 each egg), and from Erythromma najas-eggs in /Vuphar-stalks 

 Bagsvaerd So (1 spécimen in each egg) — thus in the large eggs 

 of Dytiscids as well as in the small ones of Odonates. 



(1) Revue Russe d'Entom., XVI, 1917, p. 211-224. 



(2) Eut. Month. Mao. (2) IX, 1898, d. 152. 

 (3)L. c, op. 215-224. 



(4)L. c, p. 138. 



(5) întem. Revue ges. Hydrobiol. und Hydrogr. III, 1910, p. 115. 



