226 SIDNE7 F. HARMER. 



British Museum, for the opportunity of studying which my 

 best thanks are due to the Director, Professor E. Ray 

 Lankester, and to Mr. Kirkpatrick, who has shown me not a 

 little kindness in giving me information ; (4) one or two 

 specimens in the collection of the Manchester Museum; (5) 

 specimens sent to me from Jamaica by Mr. J. E. Duerden, 

 and from Victoria by Professor W. Baldwin Spencer, to both 

 of whom T desire to express my indebtedness, as well as to 

 other friends who have unsuccessfully attempted to procure 

 specimens of Steganoporella. 



Steganoporella is a genus of very striking appearance; 

 and, as has happened in many other cases, its generic cha- 

 racters are so distinctive and conspicuous that the specific 

 characters have not hitherto received due attention. Thus I 

 believe that the forms described by various writers as S. 

 magnilabris. Busk, belong to a number of different species, 

 and, in place of the two recent species given in Miss Jelly's 

 catalogue,^ I am able to define no less than twelve species. 



The only author who seems to have published the opinion 

 that most specimens of this genus are not necessarily to be 

 referred to S. magnilabris is Jullien,^ who further alludes 

 to two undescribed species Avhich he has dredged on the 

 coast of Liberia. It is probable that these are not included 

 in the material which has been at my disposal. 



The Polyzoa belonging to this genus are characterised by 

 the large size of the zocecium and of the operculum. The 

 zocecium consists of a calcareous basal wall and four vertical 

 walls, which will be described as, respectively, proximal ( = 

 aboral), distal, and lateral. The proximal and distal walls 

 are commonly somewhat oblique, their free edges being 

 situated more distally than their base-lines. The sixth or 

 ^' upper" surface is covered, as in the Membraniporidae, by a 

 chitinous membrane or ectocyst, the " epitheca " of most 



• ' Syn. Cat. Recent Mar. Bryozoa,' 1889. I give below my reasons for 

 referring Membranipora delicatissima, Busk, to Siphonoporella, 

 Hincks. 



» 'Miss. Sci., Cap. Horn,' vi, Zool., 1888, p. I. 79. 



