of the Fishery Board for Scotland. 291 



1862. Daphnia cucullata, G. 0. Sars, Oin Crust. Clad, iagttagne i Omegnen af 

 Christi. 



1866. Hyalo-daphnia berolinensis, Schodler, Archiv. fur Naturges., p. 24, pi. ii. 



fig. 8 ; pi. iii. fig. 15. 

 1884. Daphnia cucullata, Herrick, loc. cit., p. 63. 



This is distinguished from other British Daphnids by the head being 

 produced upward to a sharp point. 



Bosminid^e. 



Bosmina, Baird. 



Bosmina longirostris (Miiller). 



1776. Lynceus longirostris, Miiller, Zool. Dan. Prod., No. 2394. 

 1861. Bosmina longirostris, G. 0. Sars, Om de i Omegnen af Christi. forekom. 

 Clad., p. 11. 



1867. Bosmina longirostris, Nor. and Brady, Nat. Hist. Trans, of Northumb. 



and Durham, vol. i. p. 357, pi. xxii. fig. 4. 



This is a small species. The anterior antennae are comparatively long and 

 curved. It occurs sometimes in considerable abundance. 



Bosmina longispina, Leydig. 



1850. (?) Bosmina longirostris, Baird, Brit. Entom., p. 105, pi. xv. fig. 3. 

 1860. Bosmina longispina, Leydig, Naturges. der Daphn., p. 207, pi. viii. 



fig. 62. 

 1867. Bosmina longispina, Nor. and Brady, loc. cit., p. 358, pi. xxii. figs. 1, 2. 



This a much larger species than the last, being about double the size. 

 The anterior antennae are not so curved and proportionally stouter ; the 

 spines of the postero-ventral angle are longer and stouter ; the outer or 

 convex margin is frequently furnished with two indistinct notches ; the 

 surface of the carapace is faintly striate longitudinally and sometimes 

 reticulate. This appears to be the form described by Baird. The two 

 species come very near each other, and may be only forms of one. I 

 found both forms in Loch Balnagowan, Lismore Island. 



Lyncodaphnia. 



Ilyocryptus, G. O. Sars. 



Ilyocryptus sordidus (Lievin). 



1858. Acanthocercus sordidus, Lievin. 



1863. Acantholeberis sordidus, Norman, Ann. Nat. Hist., ser. iii. vol. xi. pi. xi, 



figs. 6-9. 

 1861. Ilyocryptus sordidus, G. 0. Sars, op. cit., p. 12; Andet Bidrag., p. 34 



(1862). 

 1867. Ilyocryptus sordidus, Nor. and Brady, loc. cit., p. 368. 



Ilyocryptus is apparently not a swimmer. I did not observe any of those 

 captured making even an attempt to swim though kept alive for several 

 days; but if clumsy in their movements, which consisted of a kind of half- 

 crawling, half-tumbling process, they were by no means inactive. Adult 

 specimens were usually more or less coated with mud. 



LYNCEIDiE. 



Eurycercus, Baird. 



Eurycercus lamellatus (Miiller). 



1776. Lynceus lamellatus, Miiller, Zool. Dan. Prod., No. 3396. 



1850. Eurycercus lamellatus, Baird, Brit. Entom., p. 124, pi. xv. fig. 1. 



1884. Eurycercus lamellatus, H«rmk lo sit., p. 80, pi. H, figs. 5, 6. 



