BRANCHIOPODID.E. DAPHNIID^E. 101 



A week later, Oct. 4, Mr. Vallentin revisited the pond hi 

 the hope of obtaining further specimens, but without success,, 

 and he wrote : "All the Chirocephali had vani.-hcd 1'rom the 

 roadside pond. I most carefully worked with my hand-net 

 all over the pool, but not a single Chirocephalus could I find. 

 On thinking this matter over, I imagine that a herd of cattle 

 on their way to Helston Market to-day being market day- 

 had rushed through the pool and killed all the specimens. 

 The little pond was about, say, 8 feet by 6 feet ; the sides 

 were trampled down, and there were numerous marks made 

 by cattle." (7?. Vallentin in litt.~) 



Suborder III. Cladocera. 



The following works will be most frequently quoted in the 

 account of this suborder : 



T850. BAIRD (W.). Natural History of British Eiitomostraca. 



1867. NORMAN (A. M.) and BRADY (G. S.). Monograph of the British 

 Entomostraca belonging to the Families BosminicUe, Macrothrieid.se, 

 and Lynceidne. Nat. Hist. Trans. Northurnb. and Durham, vol. i. 

 pp. 354-400, pis. xviii.-xxiii. 



1900. LILLJEBOKG (W.). Cladocera Suecioe. 



Tribe I. CALYPTOMERA. 



Fain. 1. S I D iDuE. 



SlDA CRTSTALLINA (0. F. Mu'ller). 



Exeter Canal ; River Otter (.4. M. JV 7 .). 



Fam. 2. D A P H N 1 1 D JE. 

 DAPHNIA PULEX (de Geer). 



Very common. Var. obtusa, P. E. Miiller ; St. Ives 

 Vallentin !). 



DAPHNIA LONGISPIXA (0. F. Miiller). 



1850. Daphnia pule:r, var., Baird, pi. vii. figs. 3, 4. 



1895. Daphnia lomjispina, Th. Scott, Thirteenth Ann. Rep. Fish. 

 Board Scotland, p. 190, pi. v. tig. 1. 



1898. Daphnia l<ni</ixpiu<i, G, S. Brady, " British Species of Ento- 

 mostraca belonging to Daphnia and allied genera," Nat. Hist. 

 Trans. Northumberland, Durham, and Newcastle-upon-Tvne 

 vol. xiii. p. 228, pi. viii. tigs. 11-19. 



1900. Daph/ii/i luityispina, Lilljeborg, p. 94, pi. xii. fig. 14, pi. xiii. 

 tigs. 1-8, pi. xiv. tigs. 1-9. 



