THE GENERA OF NEMERTEANS. 211 



tapered posteriorly. Proboscis extremely slender. The thick 

 muscular coats of the body-wall are tinged red. 



9. Borlasia elizahethae Mac Intosh. 



Synon. V Ophiocephalus murenoides delle Chiaje. 



No eyes , body hardly flattened dorso-ventrally, generally 

 with numerous wrinkles on the surface. I found specimens 

 in which the head was white and speckled with green as 

 described by Mac Intosh , others in which it was of the 

 same purplish brown colour of the body. The white cross- 

 belts were sometimes distinct , sometimes very faint indeed. 

 Urticating elements in the proboscis. 



Genus Cerebratulus Renier. 



Body more or less flattened. Proboscis generally with 

 a cross of fibres at each pole in transverse section. Eyes 

 not very developed , rarely numerous. Urticating elements 

 of different size in the wall of the proboscis. In several 

 species four longitudinal nerve trunks in the proboscis. In 

 others there is a very delicate caudal appendage. 



10. Cerebratulus marginatus Renier. 



Synon. ? Fasciola angulata 0. F. Muller. 

 Serpentaria fragihs Goodsir. 

 Meckelia somatotomus Leuckart. 

 PoUa siphunculus delle Chiaje. 

 Cerebratulus" angulatus Mac Intosh. 



» grandis (Sars) 0. Jensen. 



Lineus beattiaei Gray. 

 Meckelia olivacea Rathke. 



This is in Naples the most common species and can attain 

 considerable dimensions. A spirit-specimen is in my posses- 

 sion in which the width of the body close to the tail 

 measures 30 mm. In colour it varies from a whitish grey 

 or brown to a dark steelblue. There is no difference in 



Kotes Ironi the Leyden Miisevini. 



