172 BRITISH ENTOMOSTRACA. 



Hah. — Dredged in from eighty to ninety fathoms of 

 sand ; twenty miles east of the Noss in the Shetland Isles ; 

 R. M'Andrew, Esq. 



9. Cythere inopinata. Tab. XX, figs. 1, \a-e. 



Cytheke inopinata, Baird, Zoologist/i, 195, f. a, b; Trans. Berw. 

 Nat. Cluh, ii, 153. 



Shell oblong ovate, nearly of equal size at each ex- 

 tremity ; white, with a slightly orange-coloured mark on 

 the upper edge; transparent, smooth, and shining ; perfectly 

 free from hairs, but possessing a few short, spinous pro- 

 jections on the lower margin of the posterior extremity. 

 Each valve has a gibbous projection about the middle, 

 which is best seen when the animal is lying on its back, 

 and is sinuated on the interior margin. 



The superior antennae (f. 1 h) are composed of five (?) ar- 

 ticulations, and furnished with several rather short seta3. 

 The inferior or pediform antennae (f. 1 c) are provided with 

 a stout, jointed seta. This species is very small, and from 

 this cu'cumstance and its always creeping at the bottom, 

 is easily overlooked. 



This is the second species only that has as yet been 

 found inhabiting fresh water, Mr. Say having previously 

 described one as occm-ring in Georgia and East Florida. 

 See ' Jom-n. Acad. Nat. Sc.,^ Philad. 1817. 



Hab. — The only place I have ever found this species is 

 in a small pond between Hanwell and Southall, Middlesex. 



10. Cythere angustata. Tab. XXI, fig. 6. 



Cytherina angustata, Munster, Jalirbuch fiir Mineralogie, 1S38, 



t.6, f. 10. 



Shell oval oblong, obtuse at either extremity, narrower 

 anteriorly, and slightly sinuated on inferior margin. It 

 is of a pale yellow colour, and the surface is shining and 

 polished-looking, but when examined by the microscope, 

 it is seen to be covered with small asperities. The sub- 

 stance of the shell is horny-looking and transparent. 

 Along the dorsal margin, on each side, there is a scries of 



