206 SYLLIS BUSKIL 



three minute points between. In segments 45 — 53 stout bristles with, a simple terminal 

 piece are present. In segments 54 — 62 are bristles like those in front (with long 

 slender terminal pieces), besides two simple bristles, the one with an entire point, the 

 other with a bidentate tip. 



In large examples (5 cm. long and 125 segments) from Villerville there were in front 

 twenty-seven segments with long bidentate tips to the bristles ; the next fifty-six segments 

 with two ypsiloide bristles ; the twenty-five following with one ypsiloide bristle, and one 

 bristle with a short unidentate tip ; and the last sixteen with a long bidentate tip to the 

 bristles, as in the anterior segments. He also met with an example in which regeneration 

 had taken place, but to a less degree than in Mesnil's example. 



He dredged 1 an epitokous female of 32 segments, somewhat resembling his Syllis 

 altemosetosa, at Cannes. It had a rounded head, with four enormous eyes, and three 

 slightly articulated tentacles. The first segment bears a dorsal cirrus of ten articulations, 

 a ypsiloide bristle, a bidentate one, and a ventral cirrus. The bristles vary posteriorly, 

 and swimming-bristles with hooked points were present from the second to the thirtieth 

 segment. A median papilla occurred between the anal cirri. 



Mesnil 2 relates a case of regeneration of the head with four eyes furnished with 

 lenses, and the anterior region with complete pharynx, proventriculus, and other organs. 

 The posterior part of the new region, that is, where it joined the old, presented very 

 indistinct segmentation. He notes that about the seventh regenerated segment anteriorly 

 a simple bristle, curved and bifid at the extremity, occurred, whereas he had not found 

 such in the ordinary or unregenerated example. 



Gravier (1901) pointed out the presence of a third kind of bristle, viz., one with a 

 spike on the dilated end of its stout shaft, and a short distal piece. Such may indicate a 

 stage in the modification of the stronger forms devoid of the terminal piece. This author 

 also describes and figures a female stolon of thirty-five segments and 10 mm. in length. In 

 this the usual conditions are found. The long natatory bristles are tapered towards the 

 extremity and hooked. The stout ventral bristles show a tooth between the bifid ends 

 and minute spikes in the hollow. 



A female bud, with four enormous eyes, and greyish eggs in the body-cavity, has 

 more recently (1906) been mentioned by De St. Joseph. 



10. Syllis Buskit, 3 n. s. Plate LXX, fig. 23— foot ; Plate LXXIX, figs. 18 and 18 a— 



bristles. 



Specific Characters. — Head apparently typical and with large palpi. Eyes had dis- 

 appeared in the preparation. Tentacles and cirri articulated and of considerable' length. 

 Body of comparatively large size, 1-g- in. long, the general aspect being that of Syllis 

 armillaris. Foot presenting dorsally a comparatively long articulated cirrus of 24 — 28 



1 ' Ann. Sc. Nat./ 9 e ser., t. in, p. 183 (1906). 

 3 < Compt. rend. Soc. Biol./ t. liii, p. 269 (1901). 



8 Named after Professor G-. Busk, who encouraged others, and also did much able work in the 

 Polyzoa and other groups. 



