REPORT ON THE POLYZOA. 13 



poridse as Amphiblestrum crlstatum, it would appear best to retain both in Memhrani- 

 pora until generic characters can be found for the group. Memhranipora tripunctata, 

 Waters/ belongs to the same group. 



Thalamoporella steganoporoides, Goldstein (PL I. fig. 15). 



Vincularia steganopm-oides, Goldstein, Proc. Roy. Soc. Victoria, p. 6 (sep.) pi. ii. fig. 5, 1881. 

 Vincidaria gothica, Busk, Zool. Chall. E.Kp., part xxx. p. 72, pi. xxiii. lig. 1. 



Two out of four Challenger specimens have a small triangular avicularium at one of 

 the lower corners of the zocecium. In some parts these avicularia are fairly abundant, 

 in others rare. The central arch or lip is formed, as described by Busk, through the 

 coalescence of the basal and two lateral growths, but even when fully matured parts are 

 calcined sutures are seen between the three processes. 



The Vincularia gothica, d'Urbiguy, is much smaller than the Challenger form, and 

 it would be impossible from the description and figure to say whether it represents 

 Vincularia labiata or Vincularia gothica of Busk, even if it be identical with either. 

 Memhranipora gothica, Busk,^ cannot be the same as the present species on account 

 of the difierent type of avicularia, and there is also the Cellepora gothica of Hagenow, 

 so that it will be safer at present to retain Goldstein's specific name, 



Thalamoporella labiata, Busk (PI. I. fig. 23 ; PI. II. figs. 12-15, 33). 

 Vincularia labiata, Busk, Zool. Chall. Exp., part xxx. p. 73, woodcut, lig. 3. 



Sections prepared show the rosette plates with a very large watchglass-shaped cal- 

 careous protection on the one side. In my description of Chorizopora brongniartii,^ I 

 mentioned that the connecting tubes terminate with a convex end in the upper part of 

 the zocecia, but concave on the lower. Since then Vigelius* has figured these " halbkugel- 

 formio-e Ausbuchtungen" in Flustra, and Levinsen' also gives a diagram, confirming 

 what I have written as to the value of the characters which these rosette plates furnish 

 in specific determination. 



Dr. Jullien® proposes a new name "origella" for all " les bourgeons de I'endocyste," 

 and divides them into " origelles evolutives," represented by the growths from the various 

 rosette plates, and into " origelles abortives," representing the surface pores, and other 

 perforations, and would like to see classification largely based upon what he calls the 

 origella. 



1 Ann. and Mag. Nat. Hist., ser. 5, vol. xx. p. 184, pi. v. figs. 12, 18, 19, 20. 



- Quart. Journ. Mia: Sci., vol. iv. p. 176, pi. vii. figs. 5, C, 7. 



' Ann. and Mag. Nat. Hist., ser. 5, vol. iii. p. 35. 



■> Die Bryozoen gesammelt wiihrend der dritten und vierten Polarfahrt des "Willem Barents," p. 21, &c. 



^ Bryozoer fra Kara Havet, 188C. 



« Bryozoaires, Mission du Cap Horn, loc. cit., p. 12. 



