550 Dr. W. G. Ridevvooa on 



14. P. revoili, Robin*. — Erythrea ; Somaliland ; British East 



Africa ; Uganda. 



15. P. cnpensis, Smith. — From Zambesia, south to Transvaal, Zulu- 



land, Natal, and Pondoland, west to Mossamedes and 

 Benguela. 



16. P. damai-e7isis, Pet. — Damaralaud ; Namaqiialand ; Lake Ngami ; 



Tette. 



17. P. d. brockmani, K. A. — Erythrea; Somaliland. 



18. P. d. media, K. A. — Abyssinia (Harar). 



19. P. yambiennis, K. A. — Gambia. 



LXV. — On Specimens o/ Ceplialodiscus iiigrescens supposed 

 to have been dredged in 18 U or 1842. By W. G. Ridewood. 



The genus Cephalodisais was founded upon material dredged 

 by the 'Challenger^ iu 1876 from a single locality (Station 

 311) in the Straits of Magellan. The full report upon that 

 material t was drawn up by Prof. W. C. M'Intosh and 

 Dr. S. F. Harmer, and published in 1887 (5), the species 

 being described as Ceplialodiscus dodecalophus. 



Since then twelve new species of Cephalodiscus have been 

 described : — C. gracilis, C. sibogce, and C. levinseni, by 

 Harmer (3) ; C nigrescens, by Lankester (4) ; C. gilchristi 

 and (/. hodgsoni, by Ridewood (6 and 7) ; C. eequatus, C. in- 

 ceguatus, C. solidus, C. densus, and C. r«?'«5, by Andersson (i) ; 

 and C. indicus, by Schepotieff (9). 



Another species, somewhat resembling the C. rarus of 

 Andersson, is stated to have been obtained on the second 

 Frencli Antarctic Expedition. The name given to it by 

 Gravier (2) is C anderssoni ; but since the author does not 

 enumerate its distinguishing features, the species cannot as 

 yet be regarded as more than a nomen nudum. 



Yet another species, of strongly marked facies, was 

 obtained by the ' Scotia ' during the Scottish National 

 Antarctic Expedition, whe>i at Station 34-6 (lat. 54° 25' S., 

 long. 57° 39' W., depth 56 fathoms), in December 1903. 



* Bull. Soc. Philom. (7) v. p. 90 (1881). Name perhaps antedated by 

 Heuglin's Nycteris lahiata (N. Act. Ac. C. Leop.-Car. xxix. p. 5; 1861), 

 the type of which I have not yet seen. 



t The full report was preceded by a preliminary notice in the ' Annals 

 and Magazine of Natural History,' (5) x. 1882, pp. 337-348, and another 

 in the lleport of the British Association meeting of 1882 (published 1883, 

 pp. 596-597). The first published figures of Ceplialodiscus, made from 

 drawings supplied by Prof. ]M'Into.sli, appeared in E. R. Lankester's 

 article " Polvzoa "' in the * luicvclopaedia Britannica,' ed. 9, xix. 1885, 

 figs. 8-10. 



