AMPHITRITE. 245 



PLATE XXXIII. 



Fragment of an Amphitrite bombyx, being the same as Plate XXXII. fig. 8, 

 with the plume regenerated and enlarged. 



3. AMPHITRITE FLOSCULA. Plate XXXI. Pig. 9. 



Animals which are modelled after the same general type by nature, 

 are sometimes distinguished by strange peculiarities, of which the sub- 

 ject of this paragraph is an example. Yet, its rarity has precluded me 

 from investigating its history with sufficient precision. The more ob- 

 scure and equivocal any genus or species of living creatures may appear 

 to the naturalist, the greater the number of specimens are required to 

 satisfy him. 



Though smaller than either of the preceding, which are both of great 

 interest, the Amphitrite floscula surpasses them in beauty ; nor is it infe- 

 rior to them in certain singularities, and all of which merit much farther 

 notice than it has been in my power to bestow on them. 



In general formation this creature resembles the ventilabrum and 

 bombyx, consisting of a vermicular body, crowned by a branchial plume. 

 It extends two inches in whole, of which the latter is equivalent to about 

 a fourth part, and consists of thirty-two branchiae, disposed in two vertical 

 compartments, forming together a circular funnel as before. The branchiae 

 are composed of a rib, bare towards the summit, and fringed on each 

 side with cilia of unusual length, inclining inwards. The tip of the rib 

 itself is incurved. A transparent elastic web connects the branchiae with 

 each other below ; and the whole form a perfect funnel, with an incurva- 

 ture of the tip. I have been unable to detect antennulae in the centre, 

 such as are borne by the others. If present, they are minute or colour- 

 less. The body consists of a number of segments with interannulations. 

 Thus, a narrower ring is interposed between two which are broader and 

 of greater diameter. 



I have been also unable to discover whether there is a row of any- 

 thing resembling pencils on the sides, but I sometimes thought a row of 



