206 BRITISH HYDRACHNID^. 



It will be seen from the above that the genus we are now about 

 to consider varies very much from those we have previously men- 

 tioned. All of the previously noticed Hydrachnids have swim- 

 ming-hairs to the second, third, and fourth pair of legs, and in some 

 cases to the first ; but in the genus Eylais the fourth pair are des- 

 titute of swimming-hairs, which to a swimming mite would appear 

 to be a very desirable and necessary addition. The fourth pair of 

 legs are strong and very hairy, but are quite without those long 

 hairs we have before noticed. The eyes are also placed very near 

 each other, and not wide apart like the eyes in other Hydrachnids. 

 There is only one other Hydrachnid having the eyes in a central 

 position, and that is the Linmocharis mentioned above. 



Up to the present I believe only one species is known of this 



genus, and that is 



Eylais extendens (Miill.). 



Bibliography : — 

 1776. — Hydrachna extendens. Miiller, Zool. Dan. Prodr., p. 190, 



No. 2272. 

 1 78 1. — Hydrachna extendens. Miiller, HydrachncB^ p. 62, Tab. 



IX., Fig. 4. 

 1793. — Trombidnwi extendens. J. C. Fabricius, Ent. Syst., Tom. 



II., p. 406; p. 24. 

 1796. — Eylais extendens. Latreille, Precis des Caracthes des 



Insectes^ p. 182. 

 1805. — Atax extendens. J. C. Fabricius, Syst. Antliatorum^ p. 372. 

 1834. — Eylais exte?idens. Duges, " Remarques sur la famille des 



Hydrachnes," in Annates des Sciences Nat., Seconde Serie, 



Tom. I, p. 156. 

 1835-41. — Eylais extetidens. C. L. Koch, Deutschlands Crust. ^ 



etc., p. 14, Figs. 21 and 22. 



Also Eylais alutacea, p. 14, Fig. 20. 



Also Eylais longi?na7ia, p. 14, Fig. 23. 



Also Eylais atoviaria, p. 14, Fig. 19. 



Also Eylais conjinis, p. 14, Fig. 18. 

 1854. — Eylais extendens. Bruzelius, Beskr. 0. HydracJmides, som, 



Forek. inom Skdne, p. 52, Tab. 5, Figs. 5 — 10. 

 1876. — Eylais extendens. Kramer, Beitr. zur. Naturgesch. der 



Hydrach., p. 313, Taf. IX., Fig. 22. 



