272 HISTORY OF BRITISH CRUSTACEA. 



Gen. 142. MACROTHBIX, BaircL 



Upper antennae flat and one-jointed, pendulous from the 

 beak ; filament from end of first joint of front branch of 

 lower antennae much longer than any of the others ; * eye 

 accompanied with a black spot. 



Macrothrix laticornis, Jurine, sp. — Carapace oval, 

 transparent, colourless, smooth. 



Hab. Ponds at Southall and Highgate, Middlesex ; Bel- 

 fast. 



Near this, and probably only a rosy-coloured variety of it, 

 is a species which has been named M. roseus. It has been 

 found abundantly in Lochmaben Loch, in Dumfriesshire, 

 where it forms great part of the food of the fish called the 

 Yendace. Dr. Baird says it swims horizontally, and that 

 the motions of its arms, as it bounds through the water, are 

 soft and graceful. 



Gen. 143. BOSMINA, Baird. 

 Upper antennae long, curved, cylindrical, consisting of 



* Hence the name Dr. Baird has given it, from /xaKpos, long, and 0/n|, a 

 hair. 



