V AMPIIIPODA LAEMODirODA 1 39 



Fam. Talitridae. — This family may be distinguished by the 

 absence of a palp on the mandible, and by one ramus of the 

 uropods being very small or wanting. The various kinds of 

 " Sand-hoppers " belong here, familiar creatures on every sandy 

 coast between tide-marks. The genera Talitrus and Talorehestia 

 always frequent sand, while Orcliestia is generally found under 

 stones and among weed. Some species of Orcliestia, e.g. 0. gam- 

 marellus, live inland in moist places at some distance from the 

 sea ; one species of Talitrus (T. sylvaticus) occurs at great eleva- 

 tions in forests in Southern Australia. 



Hyale is a coastal genus, and is also found on lloating objects in 

 the Sargasso Sea. Hyalella is confined to Lake Titicaca and the 

 fresh waters of South America. Cliiltonia from S. Australasia. 



Fam. Corophiidae. — The members of this family have a 

 rather tlattened body and small abdomen, and the side-plates on 

 the thorax are small. The uropods are also small and weak. 

 Some species of the genus Corophium are characteristic of the 

 Caspian Sea. 



Sub-Order 2. Laemodipoda. 



Fam. 1. Caprellidae ^ are also chiefly littoral forms, swarm- 

 ing among rocks covered by algae, though they are by no means 

 so easy to detect as the Gammaridae and Tanaidae which haunt 



Fig. 96. — Ccqrrella (jrandimana, x 4. «, Abdomen ; r/, gills ; t, 3id (first free) 

 thoracic segment ; t' , 8lli thoracic segment. (After P. Mayer. ) 



similar situations. In a basinful of algae or Polyzoa taken from 

 the rocks fringing the Bay of Naples, the latter are easily collected, 

 the Tanaidae always crawling out of the weeds in the direction 

 of the light, while the Gammarids dart about in all directions ; 

 but the Caprellidae, with their branching stick - like forms, 



^ Cf. P. Mayer, Fauna u. Flora G. von Ncafcl, Monogr. vi., 1882 ; xvii., 1890. 



