132 SIDNKY F. HABMER. 



(8) Smitt.— " Om Hafs-Bryozoeriias utveckling och fettkroppar," 



' Ofvers. af K. Vet.-Akad. Forhandl./ 1865, No. 1, p. 9, pi. i, 

 figs. 15 — 18. 



C. eburnea (pars). — 



(9) Smitt.— " Krit. forteckn. ofver Skandinaviens Hafs-Bryozoer," I, 



'Ofvers. af K. Vet.-Akad. Forhandl.,' 18G5, No. 2, pi. xvi, figs. 

 10, 11, 13—19. 



(6) Busk.— PI. ii, figs. 1, 2 ; pi. v, figs. 1, 2. 



(7) HiNCKS.— P. 420, fig. 21 (p. 416). 

 C. eburnea, forma eburnea. — 



(10) Smitt. — " Bryozoa marina in regionibus arcticis," ' Ofvers. af K. 



Vet.-Akad. Forhandl.,' 1867, No. 6, pp. 444, 461. 



(11) Smitt. — " Recensio Syst. Bryozoorum Novaja Semlja," ibid., 1878, 



No. 3, p. 12. 



(12) Smitt.—" Recensio Bry. e mari arctico," ibid., 1878, No. 7, p. 23. 



(13) Fkeese.— " Beschr. Ostsee Bryozoen," 'Arch. f. Naturg.,' 54, 



Jahrg., Bd. i, 1888, p. 31, pi. ii, fig. 18. 



C. aculeata, Hassall. PJ. XII, fig. 4. 

 Zoarium of very delicate habit, resembling that of the next 

 species, from which it may be distinguished by its much 

 slenderer appearance ; the average height of well-grown 

 colonies from h to | inch, the branches with very little ten- 

 dency to curve inwards. Inter nodes usually short, often 

 consisting of five or seven zooecia ; but much longer internodes, 

 with more numerous zooecia, may occur, especially at the ends 

 of the branches. Branches usually arising from the 1st or 

 2nd zooecium of either side of an interuode, but sometimes 

 (especially in the case of internodes near the ends of the 

 branches) higher up : an interuode (especially a peripheral one) 

 may bear two or more branches. In nearly all colonies, in 

 addition to the ordinary branches, some of the internodes bear 

 long, jointed spines, which are curved inwards over the anterior 

 side of the branch ; these spines are most often developed from 

 the lower zooecia of an interuode, or at the apices of the 

 terminal internodes. Joints yellow, or colourless near the 

 growing-points. Basis rami usually short, not wedged in 

 between two zooecia. Z o oe c i a with a conspicuous, free, tubular 

 portion, bearing the aperture ; this portion is curved forwards, 



