132 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
examination in the laboratory of more than 560 Shrimps 
is that they are chiefly carnivorous in their diet. We find 
in their stomachs :—Crustacean remains, such as Amphi- 
pods, small Crabs, young Shrimps, and Copepoda; alsoa 
considerable amount of Molluscan remains, such as small 
specimens of Scrobicularia alba, Cardiwm edule, and 
Tellina balthica. Annelids must also form a fair pro- 
portion of their food from the number of Polycheete sete 
in the stomachs, with occasionally fragments of the tube 
of Pectinaria, and the horny jaws of a Nereid. More 
rarely the stomachs contain Foraminifera and small spies 
of Echini; and sometimes green seaweeds, minute filam- 
entous and microscopic Alez and Diatoms. We find from ' 
experiments on them in captivity that Shrimps will also 
eat practically any animal matters such as pieces of dead 
fish, other Shrimps, beef, &c. 
The male Shrimps are less numerous, and are much 
smaller than the females, and so are comparatively rarely 
caught in the nets. It is a difficult matter to determine, 
the sex in small specimens, and we find that even in fully 
formed sexually mature individuals the inner branches of 
the first abdominal appendages, which are the only exter- 
nal sexual characteristics to depend upon, do not show the 
markedly different conditions figured by Ehrenbaum.* We 
give now on Plate il. some figures showing :—(fig. 1) the 
entire second abdominal appendage of a large female 
Shrimp (22 in. long); and (fig. 2) the entire first abdominal 
appendage of the same Shrimp to show the modification of 
the endopodite or inner branch (en.) which is shown more 
highly magnified in fig. 3, in the adult female; also (figs. 
4 and 5,) the fully formed endopodites of the same 
appendage from two adult males (13 ins. long); while fig. 6 
* Zur Naturgeschichte von Crangon vulgaris. Berl. 1890, Taf. II., figs 
15A & B. 
