HABITS OF AMPHITRITE BOMBYX. 283 



dominates on the body. This animal dwells in a tube 

 surpassing its whole length, which is not of mecha- 

 nical construction, but is formed by a spontaneous 

 exudation from the entire surface of its body. When 

 originally produced, this tube is as clear as crystal, 

 completely displaying through its transparent walls 

 the shape of its occupant : it seems indeed altogether 

 made up of a silk-like secretion, and becomes quite 

 opake with age. The secretion whence this tube is 

 derived must be very copious, as several of them are 

 sometimes secreted by the animal, one after another. 



The Amphitrite Bombyx is a timid creature, and 

 impatient of light. On the slightest shock, the plume 

 collapses, and the animal at once retreats into its 

 abode, closing the orifice of the sheath ; but if left for 

 a little time undisturbed, it again ventures to issue 

 forth, rising slowly upward, as if to avoid deranging 

 the order of its feather-like branchiae. 



These elegant Annelidans have been observed, in 

 confinement, to spawn abundantly, covering the 

 bottom of the aquarium with quantities of ova mixed 

 up with a thin gelatinous matter. Spawning, indeed, 

 continues during most of the summer, more especially 

 during the months of May and June ; but all attempts 

 to rear the young progeny have hitherto proved 

 abortive, and a most interesting problem yet remains 

 to be solved, by ascertaining the earliest aspect under 

 which the juvenile Amphitrite makes its appearance 

 when first liberated from the egg. 



When disappointed, however, in our inquiries con- 

 cerning one interesting subject, it is gratifying to find 

 satisfactory illustrations of another. 



