ZOOLOGISCHE MEDEDEELINGEN 



UITGEGEVEN VANWEGE 

 's RIJKS MUSEUM VAN NATUURLIJKE HISTORIE 



\VG 30 



192C 



Deel V. 



te 

 LEIDEN 



Aflevering" 2. 



VIL - THREE NEW NEREIS-SVECIES FROM THE DUTCH EAST- 

 INDIES. 

 BY Dr. R. HORST. — (WITH 3 TEXTFIGURES). 



Nereis buitendij ki n. sp. 



Malacca-strait. P. Buitendijk, 1910. 



Amidst the Plankton of Malacca-strait Mr. P. Buitendijk met with a 

 small Nereis-specimen, characterized by the presence of a digitiform 

 appendage on the dorsum of the parapodia in the poste- 

 rior body-region. The worm measures 

 about 14 mm. in length. The head is lon- 

 ger than broad, trapezoidal, provided with 

 large, broad palps and two short antennae, 

 measuring about a third of the length of 

 the head. The tentacular cirri are rather 

 short, the longest of them reaching about 

 to the 6 th segment. The armature of the 

 proboscis consists of: 



I = 2 paragnaths, one behind the other. 



II = an oblique, distichous group of 10 

 paragnaths. 



IY = a transverse, tristichous group of 

 10 to 12 paragnaths. 



III = 3 paragnaths, arranged in a tri- 

 angle. 



V = o. 



VI = a round group of 10 to 12 paragnaths. 

 VII — VIII = a subtristichous belt of paragnaths. 



A parapodium of the anterior body-region consists of an elongated, 

 conical ligule, that bears a cirrus, not quite extending to its distal extre- 

 mity 5 the median ligule and the anterior lip of the dorsal lobe also have 

 a conical shape, whereas its posterior lip is short and convex. In the 

 ventral lobe the posterior lip is bluntly conical, not quite as long as the 



(4— XL1 — 1919) 



