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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 suffer themselves to fall by the mere effect 

 of their weight. These animals, which live on animalculae, 

 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 themseh^es 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. Bosc 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 

 ordinaiy 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 j'^odura 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 



