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When their jaws are cut off, the same thing hap. 

 pens. New bones are reproduced, new teeth, new 

 cartilages, veins and arteries. From the wonderful 

 reproduction of so many parts in this, may we not 

 extend our enquiry to other animals of equally corn-- 

 plicated structure ? Let us enquire first concerning 

 Tadpoles. If the whole of their tails be cut off, they 

 sink to the bottom of the water, and perish. But 

 if part only, they soon recover it. In one sum- 

 mer's day, the reproduction makes a rapid progress 

 in young Tadpoles. And in a short time, the new 

 part of the tail and the old together equal the tail 

 of others born at the same tirne. A second, third, 

 and fourth reproduction constantly follows, upon a 

 second, third, or fourth section. Nay, successive 

 regenerations never fail, as long as the Tadpole keeps 

 its tail. 



If 110 nourishment is given Tadpoles, they do not 

 grow, nor are the membranes of the infant state cast 

 oif. Yet the tails cut off, will be reproduced nearly 

 in the same time. 



If the head of an earth-worm be cut off, a new 

 head is reproduced. Nay, if both the head and tail 

 are cut off from the middle part, both of them are 

 reproduced. Nor is this regenerating power soon 

 exhausted. A second reproduction being cut off, is 

 succeeded by a third, this by a fourth, that by a fifth, 

 and so on. 



The same thing takes place in another kind of 

 worm, little known, which the Abbe calls an aquatic 

 boat-worm. It is composed of rings like the earth, 

 worm, which it shortens or lengthens at pleasure, 

 and so moves from, place to place. Toward the head 

 it is as large as the largest goose-quill, and its 

 length is about a span. It lives in shallow, clear 

 water, either stagnating or flowing gently, fixing its 

 fore part in the mutt, whence it is nourished. The 

 back part reaches the top of the water, and being 



