198 SYLLIS SPONGICOLA. 



Habitat. — Procured at Jersey by Mr. Hornel. Millbay Channel, Plymouth Sound 

 (Dr. Allen). 



It was first found by Professor Grube at Triest ; whilst Claparede got it at Naples ; 

 Bobretzky in the Black Sea; the same author and Marion at Marseilles. Shores of 

 France (Baron de St. Joseph). Ceylon (Willey). Canaries; Madeira — between tide- 

 marks amongst algae — rarely (Langerhans). 



Head comparatively small, of greater transverse than antero -posterior diameter, and 

 with four eyes, the anterior and larger being the wider apart. An additional pigment-dot 

 occasionally occurs anteriorly. The median tentacle is as long, if not longer, than the 

 longest cirrus and moniliform like all the cirri. The lateral are shorter. Palpi rather 

 large, often tapered anteriorly. Tentacular cirri considerably shorter than the median 

 tentacle, the upper longer than the lateral tentacles, the ventral shorter. 



Body of the typical form, segments 76 — 90, considerably tapered posteriorly, and 

 ending in two cirri with a median papilla. The general hue is translucent yellowish with 

 a brownish tinge from the intestine posteriorly, the tail, however, being translucent bluish. 1 

 The proboscis occupies the first eleven segments, the proventriculus commencing in the 

 twelfth, and extending for seven segments behind it. 



The first foot has the bifid strong hooks with occasionally a simple one (Claparede). 

 The typical foot presents the comparatively short tapering cirrus. Beneath is the short 

 obliquely-conical setigerous region with the spines passing to the upper angle. The 

 bristles are simple, of a peculiarly hamate character (Plate LXXIX, fig. 15) — somewhat 

 like a bill-hook, often bifid at the tip, the distal spikes apparently being longer in those 

 uninjured by wear. The spines generally present a curved tip. The ventral cirrus 

 is rather slender and conical, and its tip does not reach the extremity of the setigerous 

 region. 



In a pelagic female bud the foot (Plate LXX, fig. 21) has the simple bristles in the 

 setigerous region somewhat longer, whilst a long tuft of swimming-bristles occurs beneath 

 the dorsal cirrus. A spine, moreover, supports the base of these. 



In a new Syllid recently described by Gravier 2 from Madagascar the bristles some- 

 what resemble the foregoing, each being simple, and terminating in an enlargement 

 obliquely bevelled, as if the distal piece had been lost. 



Body. — Marion and Bobretzky note that the colour is variable, the young being very 

 transparent, whilst the adults are of a fine orange, sometimes opaque. 



Reproduction. — De St. Joseph 3 found that at the reproductive period the eggs fill 

 segments 28 — 81, and that natatory bristles appear, whilst the segmental organs are 

 indicated by two black points. The latter organs open on the one hand into the 

 body-cavity, and on the other at the base of the feet, the apertures in each case being 

 ciliated. The ova give the specimens a violet hue. He quotes Albert as having seen a 

 bud without a head, detached, which swam away. Malaquin 4 refers to the same 

 quotation, and calls the bud acephalous, and he has followed its further history. 



1 Claparede states that its pigment is continuous. 



3 ' Compt. Bend. 6 e Congres internat. ZooL, Berne/ 1904, p. 372, fig. 5. 



3 < Ann. Sc. Nat./ 7 e ser., p. 143. 



4 Op. cit., 1893, p. 333. 



