THE ANNALS 



AND 



MAGAZINE OF NATURAL HISTOEY. 



[EIGHTH SERIES.] 

 No. 94. OCTOBER 1915. 



XXX. — Observations on the Cape Ceplialodiscus (C. gilchristi, 

 Ridcioood) and some of its Early Stages. By J. D. F. 

 Gilchrist, M.A., Ph.D., D.Sc. With an Appendix by 

 Sidney F. Harmer, Sc.D., F.R.S. 



[Plate XI.] 



During the course of the marine biological survey under- 

 taken by the Cape Government, a species of Ceplialodiscus 

 was found at various localities on the South-African coast, 

 but most abundantly on an area of mud on the south coast. 

 The primary object of the survey being a practical one, this 

 area, which proved to be extensive and of great commercial 

 value, was thoroughly examined and tested by means of the 

 trawl ; numerous specimens of Cephalodiscus were therefore 

 readily procured, and these were forwarded to the British 

 Museum, where they were examined and reported on by 

 Ridewood (4), who described them as C. gilchristi. As the 

 object of the survey was attained and private trawlers from 

 Europe began to develop the new fishing-ground, the exploring 

 work of the Government trawler was suspended. It is still 

 possible, however, to procure specimens, though not so readily 

 as before, and I am indebted to Mr. Wadner, the manager of 

 one of the trawling companies, for the facilities which he has 

 put at my disposal for procuring additional material, on which 

 the following observations are based. The object of this 



Ann. & Mao. N. Hist. Ser. 8. Vol xvi. 17 



