9 8 



I refer the following specimens, in the collection of the University Museum of Zoology, 



Cambridge, to the present species : — 



Torres Straits, A. C. HADDON ColL, Reg. Feb. 24, 189S (Slides 10, 26, 96, 158). 



Ceylon, Miss L. R. TlIORNELY, Reg. Apr. 25, 1906, 70 (determined by Miss THORNELY as 



C. holdsworthii). 

 Port Denison, Queensland, Miss E. C. Jelly, Reg. May 24, 1895 (3 slides). 

 Port Denison, Queensland, Australian Museum, Sydney, Reg. Oct. 23, 1899. 

 Lifu, Loyalty Islands, A. WlLLEY Coll., Reg. Mar. 1, 1898 (determined by Miss PHILIPPS as 



C. denticulata). 

 Japan, found among rooting spicules of Enplectella marshalli, Prof. K. MiTSUKURl, Reg. 



Sept. 23, 1896. 

 Red Sea, T. HlNCKS Coll., Reg. May 13, 1899 (determined by Mr HlNCKS as C. clongata). 

 Off Fiji, Stat. 176, Challenger Coll., 1450 fathoms, Reg. Nov. 18, 1899. 



Zoarium relatively large, well branched. Internodes narrow in the proximal parts of the 

 colony; becoming broad more distally, and then commonly with a sigmoid fiexure. The frontal 

 surface of the internode has a broad, slightly convex region in which the outlines of the zooecia 

 are hardly visible. At the edges of the branch, the individual zooecia become distinct, terminating 

 in a short peristome which is abruptly bent frontally, the lateral outer margin of the zooecium 

 being often slightly carinate, the keel occasionally produced at its distal end into a point which 

 occurs at the base of the peristome. The number of zooecia in an internode may be even or 

 odd and is extremely variable ; in elongated internodes reaching a high figure. Branches given 

 off moderately high in the internode, seldom if ever from the lowest zooecium, usually not 

 lower than the third of one side. Basis ra mi more or less wedged in between two zooecia. 

 An ordinary internode may give off either one or two branches. A fertile internode typically 

 bears the ovicell near the middle of its length and gives off three branches, one on the proximal 

 side of the ovicell, the other two just distally to it. Ovicells with very numerous pores; greatly 

 dilated distally, the most prominent part being near the distal end. Ooeciostome l ) not developed. 

 Ooeciopore ] ) a transverse slit in the distal wall of the ovicell, close to the point where it joins 

 the frontal surface of the branch. Spines wanting. Joints black. Rootlets arising principally from 

 the proximal internodes, black-jointed ; occasionally terminating in a curved segment of the form 

 shown in fig. 2 -). 



The present species belongs to a group characterised by the considerable breadth of the 

 internodes; a feature which is due to the fact that the proximal ends of the zooecia extend 

 along the median sides of their predecessors, thus giving rise to the appearance of a broad 

 region, in the middle of the frontal side of the branch, between the distal parts of the preceding 

 zooecia. A number of species with the same general appearance have been described as Tertiary 

 fossils, as for instance C. h'órnesii Reuss 3 ) and C. s?/óaet/ua/is Reuss 4 ). The fossil forms occur 



1) Ooeciostome = the tube by which the larvae escape from the ovicell; ooeciopore = its external orifice (Harmer, 1S9S, 

 "Dev. Tuiuiipora", Quart. J. Mier. Sci., XLI, p. 81). 



2) Rootlets of this type have been described by Busk (1875, p. 6) in C. acropora\ and also, if I understand the description 

 correctly, by Levinsen (1912, "Stud. Cycl. Operculata", Kgl. Danske Selsk. Skr. (7) Naturv. og Math. Afd., X, 1, p. 16, note), ia a species 

 mentioned, but not described, as C. hamifera n. sp., found at some distance to the West of the Southern part of the L'nited States. 



3) Reuss, A. E., 1847, "Koss. Polyparien Wiener Tertiarbeckens", Haidinger's Naturvv. Abhandl., II, p. 54, PI. VII, fig. 21. 



4) Ibid., 1869, "Pal. Stud. alt. Tertiarschichten Alpen", II, "Foss. Anth. u. Bry. Crosara", Denkschr. k. Akad. Wiss. Wien, 

 Math.-Naturw. Cl., XXIX, 1 Abth., p. 279, PI. XXXIV, fig. 8. 



98 



