NEPHTHYDIDAE 



139 



The dorsal bristle-bundle contains homogomph spinigers ; the upper ventral bundle 

 homogomph spinigers and heterogomph falcigers; the lower ventral bundle hetero- 

 gomph spinigers and heterogomph falcigers. 



Remarks. Below the loo-m. line this is by far the most abundant Nereid in the 

 Falkland Island area. 



Family NEPHTHYDIDAE 



Genus Nephthys, Cuvier 



Body elongate, more or less quadrangular in section. Prostomium polygonal and 

 flattened. Four small tentacles. Proboscis with rows of soft papillae and a crown of 

 terminal double papillae. A pair of jaws within the pharynx. Feet biramous provided 

 vnth membranous, leaf-like lobes and simple bristles. There is a coiled, sickle-shaped 

 branchia between the two rami. 



2. 



3- 



With "lyre" bristles 



Without ' ' lyre ' ' bristles 



With posterior ventral lamella laciniated 

 With posterior ventral lamella smooth . . . 

 With 22 rows of papillae on the proboscis 

 With 14 rows of papillae on the proboscis 



N. dihranchis 



2 



N. serratifoUa 

 3 



A'^. squamosa 

 N. macrura 



Nephthys dihranchis, Grube. 



Monro, 1933, p. 56, text-fig. 24, with synonymy. 

 Occurrence. St. 939, New Zealand (i). 



Specific characters. A slender, elongate species. There are usually 22 terminal, 

 labial papillae and 22 rows of papillae. The dorsal ramus of the foot has a short, 

 bluntly pointed, anterior lamella, a longer and also pointed chaetal lobe, and a rounded 

 posterior lamella set very high and rather above the foot. In the ventral ramus the 

 anterior lamella has a short pointed upper lobe lying just below the so-called ventral 

 branchia and an inferior lobe that is scarcely indicated. Below, and extending beyond 

 the upper lobe of the anterior ventral lamella, there is a prominent chaetal lobe, and 

 behind this is the posterior ventral lamella, which is rounded and occupies the whole of 

 the back of the ventral ramus. Lyre bristles are present. 



Nephthys serratifolia, Ehlers. 



Ehlers, 1897, p. 24, pi. i, fig. 13. 

 Monro, 1930, p. 114, fig. 41 a, b. 



Occurrence. St. WS 219 (2); WS 220 (i); WS 228 (2); WS 772 (3). 



Specific characters. Size up to about 60 mm. by 4 mm. for 100 chaetigers. The 

 proboscis in all my specimens was withdrawn. Ehlers gives 20 terminal papillae and 

 15 rows with six or seven papillae in a row, the foremost being long and conical. In the 

 feet there are a rounded upper posterior dorsal lamella, a slender lanceolate lower 

 posterior dorsal lamella, a cirriform process at the base of the gill, a slender anterior 



