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wherries, without giving themselves the trouble to swim ; 
nevertheless, when they are desirous of diving, they re-enter 
their dwelling, and sutler themselves to fall by the mere effect 
of their weight. These animals, which live on animalcule, 
do not show themselves at the surface of the water, until the 
end of spring, and remain in the somewhat muddy depths, 
during the rest of the year. Their mode of propagation is yet 
unknown ; but it is certain that they do not carry their eggs 
on one of their sides, like the paguri, though, like these, they 
have the habit of lodging in the spoils of living bodies. 
The Talitri, according to M. Risso, remain in troops, and 
conceal themselves in the plants which the sea heaps upon 
the shore. Their number is always very considerable in the 
places which they frequent, and the rapid leap which they 
make at the moment when they move, causes them easily to 
be remarked. 
M. Bose informs us, that the talitri, unlike gammarus pro- 
per, are oftener out of the water than in, at least during the 
summer months. They love to remain upon the line of the 
ordinary tides, that is, in places which are covered with water 
only at the flow. Every time, that on divers maritime coasts, 
both in Europe and America, he removed the stones, or the 
debris thrown out by the sea, under which these little Crus- 
tacea remain during the day, sheltered from the sun, and in a 
humidity necessary to their existence, he observed that they 
made their escape with much activity, so that out of many 
hundreds which presented themselves to view, he could 
scarcely catch above two or three individuals. To execute 
these active movements, they bend back, under their body, 
the appendages of their tail, and then let them go at will, 
exactly like the podura among the insects. They give, if we 
may employ such an expression, continual fillips to the ground 
on which they are placed. 
The talitri live on animals smaller than themselves, or on 
