32 Mr. P. H. Gossc on new or lit tie-known Marine Animals, 



tennse. Those of the two following segments are similar in 

 length and structure, being all antenniform. 



Segments slightly incised, much broader than long. Foot 

 short, subcorneal, obtuse, and divided at the tip into three or 

 four lobes ; armed with a bundle of bristles, each of which bears 

 a terminal hook very freely jointed on an oblique knob. Supe- 

 rior cirrus shorter than the breadth of the segment, tapering, 

 not moniliform. Inferior cirrus scarcely projecting beyond the 

 foot, ovate and leaf-like. 



The bundles of hooked bristles consist of about sixteen each, 

 but those near the tail appear to have only about twelve. I can- 

 not find any accessory pencil of fine hairs by the closest pressure ; 

 but the long slender pair of internal plates are present. 



The internal surface of the head-lobes is clothed with vibratile 

 cilia, by the action of which a strong uniform current is drawn 

 into the mouth. The current passing down along the antennse 

 may at first be supposed to be produced by cilia on these organs, 

 but I could not detect any on close examination. The inferior 

 surface of each foot is also strongly ciliated, and vortices are 

 produced on each of these organs, the whole forming a powerful 

 current from head to tail. 



This is one of the species that increase by spontaneous divi- 

 sion from the posterior portion of the body. There was, at the 

 tail of the specimen described, an incipient young one of about 

 five or six segments, triangular in its general form and little de- 

 veloped, but well separated, by an incision, from the parent. 



This species I frequently found in my glass jars of sea- water 

 at llfracombe, especially in those in which I was keeping the 

 Hydroid zoophytes. It climbs to the surface, and then along 

 the very edge of the water, forms a slender membranous tube 

 attached to the glass, open at each end, within which it dwells. 

 If touched at either extremity, it issues forth at the other with 

 much agility, wriggling its segments in lateral undulations. No 

 drawing was made of this species. 



Sp. 2. S, longiseta (mihi). Plate IV. figs. 14-21. 



Head not lobed ; antennse short, not moniliform ; no tenta- 

 cular cirri; feet obtuse, simple, armed with two pencils of 

 bristles, of which the inferior are twice the breadth of the seg- 

 ments; superior and inferior cirri equal, minute; inhabits a 

 membranous tube. (Fig. 14, nat. size; 15, magnified.) 



Description. — Head round, not distinctly lobed (fig. 16) ; 

 three antennse, slightly fusiform, not monihform, shorter than 

 the breadth of the head, set in a transverse line : four eyes, 

 brick-red, reniform, the inner pair set a little behind the outer, 

 and rather smaller : no tentacles or tentacular cirri. 



