196 Papers from the Marine Biological Laboratory at Tortugas. 



genus are very uncertain. Hincks (1881, p. 155) placed it in the Micro- 

 poridse, but later (1887, p. 154) he removed it from this family on account 

 of "the double layer of the ectocyst," and placed it in the Steganoporellida. 

 As we understand the latter family at present, this genus can not be included 

 in it. It will require a careful study of sectioned material to determine the 

 real position of the genus. 



Genus Steganoporella Smitt, 1873. 



Steganoporella magnilabris (Busk). 



Busk, 1854, p. 62 {Membranipora magnilabris). — Smitt, 1873, p. 15 {Steginoporella 

 elegans). — Verrill, 1900, p. 594 (Steginoporella elegans). — Harmer, 1900, 

 pp. 279-286 (revision, synonymy, and detailed description). — Levinsen, 1909, 

 pp. 167-168 (discussion of family and genus). 



Common in low water to 15 fathoms. Beautifully convoluted, frill-like 

 colonies were taken on piles and on shells, sponges, coral, etc., at 12 to 15 

 fathoms. The erect frill-like extensions are sometimes 2 inches high and 3 

 inches broad. These are bilaminate and are sometimes tubular in form. 

 The color in life varies from pink to reddish brown. 



Smitt recorded the species in Pourtales's collections from 15 to 37 

 fathoms; Bermuda (Verrill) ; other distribution given by Harmer (1. c, p. 280). 



Steganoporella connexa Harmer. 



Harmer, 1900, p. 254. 



Dead colonies of what appears to be this species were taken incrusting 

 shells at a depth of 12 fathoms. The opercula are all lost from the colony, 

 so it is impossible to make use of this important structure for identification. 

 The character of the calcification, with the junction of the median process 

 with the sides of the zooecium to form a pair of opesiulse or foramina, is 

 similar to that described and figured by Harmer. Since this connection 

 of the median process with the zooecial walls is known only in S. connexa, 

 I refer my specimens to that species. The other points, as far as I can make 

 them out on the dead specimens, agree with connexa, except perhaps in the 

 matter of size, since the zooecia in my specimens are smaller than described 

 by Harmer. There is much variation in the matter of size, however, a 

 condition also stated by Harmer to occur in connexa. Only one form of 

 zooecium can be distinguished. 



The species is known from a single locality, "John Adams Bank," 

 the location of which is somewhat in doubt, but Harmer seems to feel 

 satisfied that it is south of Abrolhos Island off the coast of Brazil. 



Genus Thalamoporella Hincks, 1887. 



Thalamoporella rozierii (Audouin). 



AuDOUiN, 1826, p. 239 (Flustra rozierii). — (?) Smitt, 1873, p. 16 (Steginoporella rozi' 

 erii). — Levinsen, 1909, p. 181 (discusses at length, with five varieties). 



Found on shell in drift and at 10 fathoms on sponges. Only small, 



unilaminar colonies without ocecia were taken. Smitt found only a single, 



small specimen in Pourtales's collections. His description of this specimen 



