274 HISTORY OF BRITISH CRUSTACEA. 



Gen. 144. SIDA, Strauss. 



One branch of lower antennae with three joints, the other 

 with two joints. 



Sida crystallina, Strauss. — Carapace elongate- oval, very 

 transparent, truncated at the lower end. 



Hab. Ponds in Northamptonshire and Surrey, and near 

 Dublin and Killarney, but not very common. 



Dr. Baird describes its motion through the water as being 

 a sort of rapid running movement. He says the animals 

 " are generally inactive, and adhere in a peculiar manner by 

 the back of their head to the side of the vessel in which they 

 are contained, remaining there for hours/' 



Gen. 145. DAPHNELLA, Baird. 



Lower antennas very large, both branches formed only of 

 two joints. 



Daphnella Wingii, Baird. — Carapace elongated, and of 

 a beautiful clear crystalline transparency. 



Hab. Ponds between Twickenham and Whitton, Middle- 

 sex, and ditch near Richmond, opposite Isleworth. This 

 species was named by Dr. Baird in honour of the late Mr. 



