208 Canon A. M. Norman on 



Genus Terebripora, d'Orbigny. 



This interesting genus, the exact position of which cannot 

 be determined until the animal shall have been examined, 

 but which is presumed to be a burrowing Polyzoon, was 

 instituted by d'Orbigny in 1841 * to include two species, 

 Terebripora ramosa and T. irregularis, which he had found 

 in shells of Calyiytrwa, Crepidula^ and Pecten off the South- 

 American coast. 



In 1865 Paul Fischer published an excellent paper on the 

 familyf , in which he enumerates all the species both recent and 

 fossil jiresumed to be referable to his ^' Famille des Terdbri- 

 porides." In this paper eight recent and fourteen fossil species 

 are recorded. Two of the recent species had been found in 

 European seas — one, Terebripora Orbigniana, Fischer, bur- 

 rowing in shells of Ostrea edidis at Arcachon, and in Conus 

 mediterruneus and Triton nodifer in the Mediterranean ; the 

 other, Spathipora sertum^ Fischer, found at La Rochelle, 

 Arcachon, and the Mediterranean in shells of Lutraria eUip- 

 tica, Cardium 7wrv(fpcnm, Pectunculus (flycimeris, and Triton 

 nodifer. In 1880 M. J. Jullien \ added another recent 

 species, T. Fischeri, which was found in a shell of Baccinum 

 from Cape Verd Islands. * 



Terebripora diiriipa;, sp. n. (PI. IX. figs. 4-7.) 



Terebripora has a mode of growth analogous to that of 

 Ilippothoa divaricata, but instead of running over the surface 

 of shells &c. as in the latter species, the whole polyzoary is 

 buried in its substance, except that the orifices of the zooecia 

 open through the surface. The thread-like connecting fibres 

 or stolons in all species hitherto described appear to be quite 

 simple, but in T. ditrupat they consist of lines interrupted on 

 one side by small lateral projecting processes (fig. 5). The 

 zooecia are not in the same plane as the connecting fibre, but 

 at right angles to it, in such a manner that they are also 

 perpendicular to the surface (fig. 6). Owing to this position 

 of the zooecia their lower portion is too deeply seated to be 

 seen with the microscope; the oral opening has a somewhat 



* d'Orbigny (A.), ' Voyage dans rAm^rique m^ridionale,' vol. vi. p. 23, 

 pi. X. 



t Fischer (P.), " £tude siir les Bryozoaires perforant de la Famille des 

 T^r^briporides," Nouv. Arch, du Museum, vol. ii. pp. 293-313, pi. xi. 



X Jullien (J.), " Desc. nouv. Espece de Bryozoaire perforant du genre 

 Terebripora, d'Orbigny," Bull. Soc. Zool. de France, 1880, pp. 1-4 and 

 woodcut (separate copy). 



