170 ANNELIDA POLYCHAETA. 



A considerable change in the shape of the feet may be 

 observed in the posterior body-region , as not only the la- 

 mellar processes gradually diminish in size, but also the 

 setigerous lobes presenting different appearance. The dorsal 

 lobe becomes broad and blunt, the ventral lobe on the con- 

 trary is conically produced. The anal segment is without 

 feet, cylindrical and its surface is longitudinally grooved; 

 between these grooves there arise ridges of the skin, pro- 

 vided along their border with papillae, which are greatly 

 developed at the lateral sides of the segment. The ventral 

 side of the anal segment is almost fully occupied by the 

 base of the anal cirri. The regenerated anal segment has 

 its surface beset with densely crowded papillae. 



In the maxillary region the dorsal side of the proboscis 

 bears two paragnathi on the median line (I) , one large 

 tooth in front succeeded by a smaller one, and on each side 

 a small triangular patch (II) of 9 to 10 teeth is to be found; 

 on the ventral side the median group (III) consists of a 

 transverse patch of about 14 teeth and 2 or 3 teeth on 

 each side, the lateral groups (IV) constitute a rather large 

 semilunar patch of about 22 teeth. The basal region bears 

 on the dorsal side a median triangular patch of 3 paragnathi 

 (V), laterally a transverse ridge (VI) occurs , not very high , 

 faintly notched in the middle ; in one specimen the middle por- 

 tion of the left ridge is wanting , this tooth was thus broken 

 up in two. On the ventral side a belt of three rows of teeth 

 occurs, those of the median series alternating with the others ; 

 in the median area two teeth are situated next each other. 



This species is closely related to N. taorica Laugh. 1 ), 

 N. Helleri Gr. 2 ) and N. camiguina Gr. 3 ). JV. Helleri 

 however is distinguished by the length of its dorsal cirri, 

 which are twice as long as the superior ligule. Our know- 



1) Canarische Anneliden: Nova Acta der K. Leop. -Carol. -Deutschen Akad. 

 Bd. XLII, p. 110, T. I, fig. 15. 



2) AnDiilata Semperiana: Mem. de l'Acad. Imp. des Sciences de St. Peters- 

 burg. Vile Sér. T. XXV, p. 81. 



3) loc. cit. p. 87, pi. IV, fig. 8. 



Notes from the Leyden Museum , Vol. XI. 



