's RIJKS MUSEUM VAN NATUURLIJKE HISTORIE — LEIDEN. 13 



short, knife-shaped appendix (fig. 2 a), the internal cavity of which ap- 

 pears to be divided in two compartments by a transverse septum. How- 

 ever in the dorsal and ventral part of the fascicle some of the bristles 

 have a cylindrical appendix, with an obtuse, club-shaped end, whereas 

 their shaft bears a couple of denticulated rows near its distal extremity 

 (fig. 2 b). In the anterior segments (2 d , 3 d and 4 th ) this appendix of the 

 setae is longer and more slender; even in the dorsal and ventral part of 

 the fascicle it is curved, sickle-shaped, resembling the neuropodial bristles 

 of the second parapodium of Psammolyce flava Kinb., whereas 5 or 6 

 denticulated rows occur at the distal end of their shaft (fig. 2 c). No 

 stylodes are present, but some cylindrical papillae, as in Psammolyce, 

 occur along the border of the foot. Especially in the third segment they 

 are rather numerous. The notopodium of the foot is small, papilliform and 

 shows a fascicle of fine, capillary setae, provided with spirally arranged 

 whorls ; on its dorsum occurs one cushion-shaped ctenidium. A slender 

 ventral cirrus, showing a constriction at a short distance from its end, 

 does not reach to the extremity of the foot. In the anterior segments 

 the] Jventral cirrus is longer and more slender, extending to or beyond 

 the~ t distal end of the foot. On the 3 d segment the first branchia appears 

 as a small triangular appendix. 



I do not hesitate to propose a new genus-name for this worm ; for it 

 cannot be ranged among Psammolyce., that is characterized by the presence 

 of cheliform bristles, a long dorsal cirrus on the third segment and by 

 the absence of ctenidia, nor among Leanira, that possesses pectinate- 

 canaliculate setae and stylodes. 



The genera of Sigalioninae may be easily recognized by the following key : 



Median antenna (tentacle) 



absent Sigalion Aud.&M.Edw. 



/Lateral antennae 

 inserted on the 



prostomium , Eulhalenessâ Darb. 



I neuropod. setae [ appendix mono- 

 Ctenidia I with I aDa 



present Icheliformappen- multi-articulate . . Sfhenelais Kinh. 



Lateral anlennae 1 J /appendix only 



fused with the 

 buccal segment 



multi-articulate. Eusihenelais Mc Int. 

 neuropod. setae 



with 

 pectin, canaliculate appendix .... Leanira Kinb 

 neuropodial setae with 



knife-like appendix Euleanira Horst. 



Ctenidia 



absent Psammolyce Kinb. 



