Vv AMPHIPODA—-LAEMODIPODA 139 
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 Valitrus and Talorchestia 
always frequent sand, while Orchestia is generally found under 
stones and among weed. Some species of Orchestia, e.g. O. gam- 
marellus, live inland in moist places at some distance from the 
sea; one species of Talitrus (7. sylvaticus) occurs at great eleva- 
tions in forests in Southern Australia. 
Hyale is a coastal genus, and is also found on floating objects in 
the Sargasso Sea.  //yalella is confined to Lake Titicaca and the 
fresh waters of South America.  Chiltonia from S$. Australasia. 
Fam. Corophiidae—The members of this family have a 
rather flattened 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 Corophiwm 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 
Fie. 96.—Caprella grandimana, x 4. a, Abdomen ; g, gills ; ¢, 3rd (first free) 
thoracic segment ; ¢’, 8th thoracic segment. (After P. Mayer. ) 
similar situations. In a basinful of algae cr 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 - lke forms, 
1 Cf. P. Mayer, Fauna u. Flora G. von Neapel, Monogr. vi., 1882; xvil., 1890. 
