28 Prof. M' In tosh's Notes from the 



conspicuous part of the hook being the long anterior face 

 and crown, occupied by a small sharp main fang and 

 numerous minute teeth above it. The anterior outline 

 below tlie main fang bounds a small bay, the prow bending 

 up to circumscribe it. The inferior outline is convex. 



The otocysts in this species belong to the second group of 

 Fauvel *, viz. to the closed series in which the otoliths are 

 formed by concentric layers of secretion in the organ. 



Amphiylena mediterranea, the tenth species, is a southern 

 type from Plymouth and Torquay. The anterior region bears 

 ten branchiae each, pinnate, with a double row of barbules, 

 the whole forming, in the preserved examples, a tuft about 

 a third the length of the body. Each filament, according 

 to De St. Joseph, consists of a double row of "cellules 

 cartilagineuses," whereas the barbules have only a single 

 row. The number of ciliated barbules appears to be about 

 thirty, and they are shorter at the base and the tip than in the 

 middle. The tip of the filament ends in a long and slightly 

 tapered process with a narrow web at the base, and it has 

 palpocils. Each branchial filament has a single vessel 

 (Claparede). 



Besides the two ciliated palps, De St. Joseph, after 

 Claparede, shows a coiled process on each side, filled with 

 brown pigment-granules, and which, after Meyer, he con- 

 siders to be a fold of the upper lip, forming a superior 

 lateral chamber on each side. 



The body is about 8 mm. in length (but some may reach 

 18 mm., Claparede), usually little tapered anteriorly, but 

 distinctly so posteriorly, and ends in a bluntly conical or 

 rounded pygidium, which bears four to six pairs of eyes. The 

 segments vary from 29-33. A [)air of spherical statocysts, 

 as mentioned by Claparede, exist in the second segment. 

 They are ciliated internally and have statoliths. Claparede 

 describes a dilatation of the oesophagus in the fourth segment. 

 The circulatory system, according to the same author, 

 consists of a contractile ventral vessel and two lateral trunks 

 ap[)lied to the alimentary canal, but he could not detect the 

 ccecal branches ordinarily seen in Sabellids, 



The first achetous segment bears four eyes in two pairs ; 

 the second segment has two statocysts having a number 

 of statoliths, besides two or three minute winged bristles 

 dorsally ; and the next seven segments have dorsal tufts of 

 bristles, the upper having narrower wings, the lower 



* Coinp. Eend. Acad. Sc. Paris, Dec. 29, 1902. 



