ON BOSMINID.E, MAOROTHK.ICIJD.E, ETC.. 381 



of Durham, and Cullercoats, Northumberland ; in Easedale Tarn, 

 "Westmorland; and Thirlmere, Cumberland (Gr. S. B.). 



8. Lynceus TESTUDiN-AKiTrs, Fischer. PI. XYIII, fig. 7 ; and 



1851. Lynceus testudinarius, Fischer. Mem. des Sav. etrangers, 

 St. Petersburg, Yol. VI, p. 191. PI. IX, figs. 3-6. 



1853. Lynceus reticulatus, Lilljeborg. De Crust, ex Ord. tribus 

 Clad. Ostra. et Copep., p. 83. PL VII, figs. 6, 7. 



1860. Lynceus reticulatus (?) and L. testudinarius, Leydig. 

 Nativrges. der Daphniden, p. 229. 



1862. Graptoleleris reticulata, G. 0. Sars. Om de i Omegnen 



af Christiania forekom. Clad. Andet Bidrag., p. 41. 



1863. Alona esocirostris, Schoedler. Neue Beitrage zur Natur- 



ges. der Ciadoeeren, p. 25. PI. I, figs. 26, 27. 



1863. Alona testudinaria, Schoedler, 1. c, p. 28, 



Carapace oblong, dorsal margin only slightly arched (except in 

 old females, when it is sometimes boldly arched) ; ventral margin 

 straight, finely ciliated ; posterior extremity truncate, infero-pos- 

 teal angle with two or three large and conspicuous teeth ; the 

 whole surface of the shell, including even the head and ros- 

 trum, marked with irregularly quadrate reticulations.- Head 

 very large, in the form of a huge hood, nearly erect, extremity 

 of the hood-formed rostrum very wide and rounded ; anterior 

 antennae short, completely covered by the hood ; posterior an- 

 tennae of moderate length. Eye very large ; eye-spot not half 

 its size. Abdomen small, short, tapering gradually to the distal 

 extremity ; no supero-posteal angle, the superior margin gra- 

 dually sloping away to the base of the claws; a row of spines 

 (so fine that they look as though they were merely setae) on 

 the edge ; terminal claws short and stout, much curved, simple. 

 Length, -^th of an inch. 



This is a very pretty little species, and very distinct from all 

 its allies. Its large hooded head ; the peculiar straightness of the 



