THE THREAD-CAPSULES. 429 



But besides these, there are other smaller capsules 

 differing in their structure. They have the common 

 oblong form of those of the Actinice, but attenuated at 

 one end, which is sometimes drawn out to a needle 

 like point, (fig. 8). Sometimes at the small (4) but 

 more commonly at the large end (7, 9, 11), there is a 

 cylindrical clear body, about one-third of the length 

 of the capsule, besides the evanescent spiral coils 

 which occupy the remainder of the cavity. 



The thread of these is furnished with a brush of 

 divergent bristles at its base, extending up a space 

 about equal to the length of the capsule (5) ; so that 

 I have no doubt of the connection of this elongated 

 body with the brush. These capsules vary much in 

 form (figs. 7 to 11), and also in size ; the largest being 

 about -g^ inch, the smallest -^ inch in length. Of these 

 latter, however, I could not discover the thread, 

 either coiled or evolved. 



The specimens readily expanded their tentacles in 

 captivity, and w^ere not at all sensitive or impatient of 

 irritation. They dsd not, however, make any attempt 

 to affix themselves by their adhering bases, but 

 remained loose at the bottom of the vessel. 



I feel no doubt that they are identical with the 

 Corijnactis Allmcuun of Mr. Thompson, described 

 and figured in Dr. Johnston's Brit. Zooph. (2nd 

 Edit.) p. 474. His single specimen differed in some 

 minute details of coloming from all mine, but in so 

 variable a species this is of no consequence. None of 

 mine have any adventitious covering, except that the 

 base was surrounded by a dense mucus, in which mud 

 had become entangled. This mucus is thrown off, I 



