181 



times as broader or narrower two-layered laminae, sometimes branched with 

 prismatic branches. 



Besides some fragments of broader and narrower, two-layered colonies from 

 Wladivostock-Nagasaki (lat. 33" 5' N., long. 128" 22' E.; lat. 33" 35' N., long. 128« 

 22' E.; lat. 33" 5' N., long. 129" 24' E.), (Telegraph-engineer Schonau), I have 

 examined some small fragments of prismatic branches from Japan, found in the 

 root-tuft of an Eaplectella sp., (lat. 32" 12' N., long. 128" 15' E. Captain Suensson). 



I have earlier although with some doubt ideritified this species with T. Smitti 

 Hincks, and therefore the figures are designated with that name. I am, however, 

 at present, inclined to think that T. Smitti is distinct from all the other species 

 here described. 



Thalatnoporella Rozieri Aud. 

 Flustra Rozieri Audouin Descript. de I'Egypte, Hist. Natur., Tome 1, explic. 



sommaire d. Planches, pag. 239. Polypes PI. 8, figs. 9^ 9^- 

 Steganoporella Rozieri Hincks, Form. 1, 2 & 3 (non. 4) Annals Nat. Hist., 



ser. 5, Vol. VI, 1880, pag. 28, PI. XVI, figs. 1, 3. 

 Membranipora Rozieri Busk, Catalogue of Marine Polyzoa, Part I, pag. 59, 



PI. LXV, fig. 6. 

 Membranipora gothica Busk, Quarterly Journal micr. Science, Vol. IV, 1856, 



pag. 176, PI. VII. figs. 5, 6, 7. 

 (PI. VI. figs. 6a-6k; PI. VI b, figs. la-3b). 

 The length of the zocecia is between 0,48 and 0,79'°™-, and the distinctly marked 

 adoral areas may be developed, sometimes even in the same colony or in the 

 same zocecium, to a varying extent and in different ways. The aperture, the size 

 of which may be contained from 2V3 to 4 times in the whole length of the zoce- 

 cium, has at least in the youngest zocecia a broad and deep sinus, which how- 

 ever in a certain variety is wholly or partly filled by a somewhat projecting lip. 

 The anter of the aperture is as a rule semi-elliptic or semi-oviform, but some- 

 times the lateral margins may be more or less approximately parallel. The 

 proximal margin of the operculum is generally provided with a continuous chitin- 

 ous sclerite, which is but rarely broken in the centre. Of the two opesiulse the 

 one as a rule only reaches the corresponding lateral wall and but seldom touches 

 the basal wall in a small curved line. The other always reaches the basal wall, 

 most frequently touching it in a closed (i. e. meeting the margin of the zooecium 

 with both ends), irregularly tongue-shaped, curved line, more seldom in an open, 

 longer or shorter line, corresponding with a larger or smaller proximal part of 

 the closed, curved line. The frontal wall of the polypide-tube is generally deeply 

 depressed proximally. 



