REPORT ON THE POLYZOA. 
11 
Habitat. — Station 172, off Tongatabu, 18 fathoms, coral mud. Off Honolulu, 20 to 
40 fathoms. 
[Australian Seas ubique, New Zealand, &c.] 
This species appears to occur under two rather distinct forms. In one (the typical) 
it constitutes a beautiful circular expansion, about one inch or more in diameter, 
composed of short bifurcating branches radiating from a central short stem (vide Brit. 
Mus. Cat., pt. iii. pi. vii. fig. la), or a more straggling growth in which the brandies, 
though still springing from a more or less excentric point, are much longer, forming 
elongated forks ( loc . cit., fig. lb), constituting a variety to which the term stricta might 
be applied. Very fine specimens of this form occur in the Challenger collection, from 
Honolulu, whilst a beautiful specimen of the radiate type was procured at Station 172, 
off Nukalofa, Tongatabu. 
In all the Challenger specimens there is rarely more than one zooecium to represent 
the lateral series, but in others there are occasionally as many as four ( vide Brit. Mus. 
Cat., pt. iii. pi. vii. fig. 4), as described by Mr. Macgillivray. The great peculiarity of the 
species, however, is seen in the coarsely pitted or foveolate surface on the sides of the 
branches, and the series of large pores or pits along the dorsal sulci ; the ocecial chambers 
also have peculiar sculpture. 
(3) Idmonea marionensis, Busk. 
Idmonea marionensis, Busk, Brit. Mus. Cat., pt. iii. p. 13, pi. xiii. figs. 3, 5; pi. vii. figs. 7, 8 
(young state); Waters, Haswell. 
1 Crisina hochstetteriana, Stoliczka, “Novara” Exp., Geol. Theil, Bd. i. p. 113, Taf. xviii. fig. 3; 
Smitt, Elorid. Bryoz., p. 6, pi. ii. figs. 11-13. 
Character.-— Zoarium slender, elongate, very sparingly branched ; stem and branches 
cylindrical or subcylindrical. Zooecia two to four in each series (most usually two) 
about 0T5 to 0'20 mm., series wide apart, 0‘7 to 0’8 mm., when entire the innermost the 
longest. Surface finely but sparsely punctured ; dorsal surface convex, with a fine 
longitudinal striation. 
Habitat. — Off Marion Islands, 50 to 75 fathoms; off Prince Edward Island, 80 to 
150 fathoms. Station 147, lat. 46° 16' S., long. 48° 27' E., 1600 fathoms, Diatom ooze. 
Station 151, off Heard Island, 75 fathoms, volcanic mud. Station 320, lat. 37° 17' S., 
long. 53° 52' W., 600 fathoms, green sand. 
1 [? Auckland, New Zealand, fossil, Stoliczka; Bay of Naples and Marion Island, Waters; 
Queensland, Haswell.] 
As I have remarked in Brit. Mus. Cat., this species seems to mark a transition between 
Pustulopora and Idmonea. The cells, however, are always disposed in rows or series on 
each side of the anterior aspect of the branch, and are for the most part deeply immersed ; 
