246 



ZOOLOGISCHE MEDEDEELINGEN — DEEL L 



XVII. — ON A REMARKABLE POLYNOID-WORM WEB ER IA 

 PUSTULATA NOV. GEN. NOV. SPEC. FROM THE MALAYAN 

 ABYSS. 



BY Dr. R. HORST. — (WITH TWO TEXTFIGURES . 



At the Stations 45 and 314, north off Soembawa, in a depth of 694 

 and 794 m, the Siboga-expedition ^dredged three specimens of Polynoïnae 

 that cannot be identified with any species, hitherto described. Unfortuna- 

 tely they are somewhat incomplete, for the]elytra as" well as most of the cirri 



are absent. One of the specimens, a 

 female containing ripe eggs, measures 

 nearly 20 mm. in length and has 

 about 40 segments. The head is roun- 

 ded, broader as long, prolonged an- 

 teriorly into the two stout basal joints 

 of the lateral antennae, that are 

 nearly as long as the head, whereas 

 their distal part is only a trifle lon- 

 ger; the species therefore belongs to 

 the group of Lepidonotidae 1 ). From 

 the middle of the head a large basal 

 joint of the tentacle arises, 

 but its distal part is ab- 

 sent. The palps are stumpy, 

 conical. Xo eyes are visi- 

 ble. Each segment bears 

 a papilliform tubercle in 

 the middle of the dorsum ; 

 this series in combination with the longitudinal rows of dorsal 

 tubercles, elytrophores, cirriphores and notopodia gives the 

 body a pustulate appearance. The parapodia are characterized 

 by the total absence of a ventral cirrus; this organ 

 is only present in the first setigerous segment (the 2 J ). It con- 

 sists of a rather stout basal part and a distal joint with 

 filiform tip, hardly extending beyond the extremity of the Fig. 2. 

 neuropodium. Each parapodium (Fig. 1) consists of a papilli- 

 form notopodium, containing only an acicula, and of a much larger neuropo- 



Fig- 4- 



1) This Journal Vol. I. p. 3. 



