INTRODUCTION. XXxiii 



ON EXUVIATION AND THE RESTORATION OF LOST 

 LIMBS. 



The fact that the throwing off of the old integumeDt and 

 its replacement by a new one during the growth of the 

 animal, takes place in all the Crustacea as necessarily 

 and as constantly as in insects during their larva condi- 

 tion, has long been known, and as long has excited the 

 admiration of all who take any interest in natural phe- 

 nomena. That an animal covered by integument of the 

 hard, solid, almost stony consistence as that of the lobster 

 and the crab, for example, should have the power of with- 

 drawing itself from its shell, leaving it, to all appearance, 

 as perfect as before, with the carapace, the abdomen, the 

 limbs, the eyes, the antennae, and even the stomachal 

 teeth, and other internal shelly organs, whole and entire, 

 and in their former relative situation and condition, is 

 one of the most interesting, and, at first sight, one of the 

 most perplexing and inexplicable, of all the phenomena 

 of voluntary action. 



The first clear and satisfactory observations on this 

 subject were made by Reaumur,* whose unexampled 

 accvu-acy and truthfulness is attested by the fact that of 

 all the observations made by himself alone, far exceeding 

 those of any other naturalist of past or present times, 

 and occupying, in their published form, numerous large 

 quarto volumes, scarcely one has ever been contravened 

 by subsequent credible observers, whilst they have formed 

 the substance of half the numerous compilations on in- 

 sect life, acknowledged or otherwise, which have appeared 

 since his time. 



* Mem. de TAcad. dus Sc. 1712, p. 226, and 1718, p. 2G3. 



C 



