A REPORT ON THE CYCLOSTOMATOUS BRYOZOA OF JAPAN. 



349 



of the ventral surface of zoarium, which inflation extends to both the sides, 

 or in case it is situated at the bifurcation point, to the surface of the bifur- 

 cation angle. Ooeciostome occurring on lateral ooecial surface, occasionally 

 also on the surface of bifurcation angle, short, directed outwards. 

 Ooeciopore circular, 0.04 mm. in diameter, overhung by a hood-like expan- 

 sion from the margin. Dorsal surface minutely punctate, transversely 

 wrinkled. That at base of stem forms a peculiary characterized and 

 sharply marked off area, which may be called the dorso-basal plate. The 

 surface of the plate is unpunctate, but is pitted by a number of small groove- 

 like depressions. 



This new species is represented in the collection by a few colonies of 

 different sizes, attached on stones. They were all obtained from shallow 

 water in Aburatsubo, close to the Misaki Marine Biological Station. Charac- 

 teristic to the species are the fork-like habitus of bifurcating branches and 

 the presence of the hood-like covering to ooeciopore. In external appea- 

 rance of zoarium, it closely resembles Crisina radians (Lamk.), though 

 entirely different in the characters of dorso-basal plate and of ovicells as 

 well as in the absence of the so-called "porous lateral windows" characteristic 

 of the form just mentioned. 



18. Tttbulipora tumida Smitt 1872. 



Tubidipora tumida, Smitt 1872 (4), 119, pi. xx, fig. 7. 

 Idmoiiea atlantica, var. tenuis, Busk 1859 (3), 146. 

 ldmotiea tumida, Waters 1904 (6), 168, pi. xxi, figs. 4. 5. 



Numerous colonies of this species are contained in the collection. 

 The localities are : off Jogashima (80 fms.), off Odawara (93 fms.), and 

 Yodomi (78 fms.) in the Sagami Sea; Kagoshima Gulf (54 fms.). In spirit 

 they are milky white, frequently with a faint pinkish tint. The ovicell and 

 the dorso-basal plate of the species appears to have hitherto remained un- 

 known, but I was fortunate enough to meet with them both. The ovicell, 

 situated close to certain bifurcation point of branches on the ventral side, is 

 an inflation with minutely punctate surface and taking up usually three 

 successive pairs of zooecial series. Ooeciostome short, projecting at a 



