NEMERTEANS 219 



whose life form and colour are unknown. Only by combining colour sketches and ob- 

 servation in life with anatomical work can the identification of the Nemerteans be made 

 with any degree of certainty. 



The complete discontinuity of the African and Falkland sector Nemertean faunas is 

 reflected in this report by treatment in separate sections. It is indeed a striking fact that 

 this discontinuity should be so complete, for the predominant form of the south — 

 L. corrugotus — was first collected at Kerguelen, and it might naturally be expected to 

 appear in the fauna of the southern extremity of Africa. Instead there has been found 

 an extension of the Mediterranean fauna to the southern hemisphere as far as Saldanha 

 Bay. This was foreshadowed by the capture of Carinella annulata in Simon's Bay near 

 Cape Town, reported by Stimpson in 1856, and it suggests that the littoral Nemerteans 

 depend upon the continuity of land rather than upon ocean currents for their dispersal. 



The pelagic forms fall naturally into a separate group on account of their structural 

 peculiarities. Some of these, such as their general transparency and expanded leaf-like 

 form, can be considered as adaptations to their mode of life ; but the anomalous position 

 of the male generative organs and the sexual dimorphism exhibited by forms like Necto- 

 nemertes must be due to deeper causes. The work of Brinkmann on the pelagic forms 

 shows how close is their relationship with the Drepanophoridae and it is curious that 

 this small family, alone among Nemerteans, should have taken to the pelagic habit. 



The synonymy of most of the known forms has been thoroughly worked out by Burger 

 in his magnificent Naples monograph (1895) and in his section (Nemertini, 1904) of 

 Das Tierreich. Synonymies are only given in the following report where fresh data 

 warrant a revised opinion on the relationship of previously described species. I have 

 followed Coe (1905) in uniting the Protonemertini and Mesonemertini of Burger under 

 the order Paleonemertea, and in retaining Hubrecht's order Hoplonemertea for the 

 armed species instead of Metanemertini. The names are less unwieldy than those pro- 

 posed by Poche (1926). The further division of the Hoplonemertea into Monostilifera 

 and Polystilifera (Brinkmann, 1917) is adopted. 



LIST OF STATIONS AT WHICH NEMERTEANS WERE 

 COLLECTED, WITH THE SPECIES OBTAINED 



In the list of stations the following symbols represent the various kinds of gear used : 



B Oblique. 



BTS Small beam trawl. Beam 8 ft. in length (2-45 m.): mesh at cod-end J in. (12-5 mm.). 



DL Large dredge. Light pattern, 4 ft. in length (1-2 m.). 



DS Large dredge. Heavy pattern, 4 ft. in length (1-2 m.). 



N 4-T Small dredge. 



H Horizontal. 



OI H I 



Nets with mesh of 4 or 7 mm. (0-16 or 0-28 in.) attached to back of trawl. 



N7-TJ 



N 70 70 cm. tow-net. Mouth circular, 70 cm. in diameter (27-5 in.): mesh graded, at cod-end 

 74 to the linear inch. 



