THE BRYOZOA 227 



The habit of growth is decidedly scrupocellarian. The branches are 

 stiff and calcareous, and the internodes rather long, varying from 3 or 

 5 in the lower part of a colony, to 12 or 15 in the upper. Both lateral 

 and frontal avicularia are developed upon each zcecium and are of 

 large size (fig. 3, lat. f.a.}. On those internodes where oecia (#.) 

 occur the frontal avicularia are pushed to one side and form an irreg- 

 ular line between the two series of cells. Commonly but one spine 

 (sp.) is developed at the upper outer angle. The opercula {op.) vary 

 from a simple, spinous process to a broad, sub-triangular structure 

 marked with the peculiar hand-like sculpturing which characterizes 

 this species. The zcecium which is situated at the bifurcation of a 

 branch possesses a short spine at the top, and in the particular case 

 represented, the aperture is partially covered by two opercula instead 

 of an operculum and a spine, as is the usual case (op., op'). In 

 comparison with a specimen from Norway, the appearance of the 

 colony is more robust, the spines are shorter and thicker, and the 

 zoecia slightly longer and broader. Fig. 4 represents the dorsal sur- 

 face. Upon the zo2cia of the lower portion of the colony, radical 

 fibers are developed, but no vibracula are visible. 



According to Mr. Hincks, vibracula are of uncertain occurrence in 

 this species. Such as are found are of a rudimentary character, and 

 he remarks : " They are commonly wanting on many of the cells." It 

 is possible that in a larger quantity of material some zoecia may be 

 found upon which vibracula or traces of such structures are present. 

 This form differs from the normal in this one particular only. Both 

 Hincks and Jullien ('82) have described as S, scabra a form which 

 not only lacks vibracula, but differs from the type in other important 

 respects, and for the present I shall be guided by the precedent they 

 have set. 



CABEREA Lamouroux. 



CABEREA ELLISII Fleming. 



Caberea ellisii HINCKS ('80), pi. vui, figs. 6-8. 

 Caberea ellisii SMITT('67), pi. xvn, figs. 55-56. 



Habitat. Found growing on a shell dredged at 20 fms. ; obtained 

 also on the rocks at low tide. 



Local distribution. Juneau ; Orca, Prince William Sound ; Cum- 

 shewa Harbor, Queen Charlotte Islands ; Vancouver Island. 



Geographical distribution. Labrador and Maine; St. George 

 Banks, 28-150 fms. ; Greenland, 100 fms. ; Iceland, 15-20 fms. ; Scan- 

 dinavia and Finmark, 50-80 fms., not uncommon; Shetland, 40-70 

 fms., abundant; Orkneys; off the coast of Antrim, 62-72 fms. 



