100 Rev. T. Ilincks on Polyzoa 



with a calcareous lamina beneath. There are usually no more 

 than two or three spines on each side, which are very tall and 

 stout, cylindrical and suberect. There are also differences in 

 the avicularium, though in both cases it is of the pedicellate 

 type. Tliat of M. cymhcrformis is borne on a very long pedi- 

 cel, to the top of which the avicularian cell seems to be articu- 

 lated ; and it is altogether more slender that that of its ally. 



Several specimens occur forming small patches on weed. 

 Smitt states that it is not uncommon in the Arctic seas, as far 

 as the north of Spitzbergcn, in 10-60 fathoms. The M. 

 lineafa of the German Polar Expedition, obtained at Sabine 

 Island, should probably be referred to this species. 



Genus Lepralia, Johnston. 



I retain for the present the genus Lepralia as Johnston 

 defined it, though well aware that, the somewhat heterogeneous 

 assemblage of forms which it includes must be broken up and 

 redistributed. 



11. Lepralia trtspinosa, Johnston, var. (PL XI. fig. 1.) 



EscharcUa Jacotini, forma lamcllosa, Smitt, Krit. Forteckn. ofver Skan- 

 dinaviens Ilafs-Bryozoer, pt. iv. (18(>7) pi. xxiv. fig. 56. 



On shell, common. 



[Davis Strait, 100 fathoms [Norman, ' Valorous ' dredg- 

 ings).] 



In the variety of this well-known species, which alone 

 occurs amongst the Icelandic dredgings, the surface of the 

 polyzoary is very flat and uniform in appearance and of a 

 dull whitish colour. The zoooecia are smooth or very minutely 

 granular, areolated round the margin, and bordered by promi- 

 nent lines ; the aperture is suborbicular, well arched above, 

 the lower lip rising in the centre into a small denticle ; the 

 margin is not at all elevated. The large pointed avicularia 

 are present as in the more usual form ; and there is also fre- 

 quently a small oval avicularium with rounded mandible on 

 one side of tlie moutli. Similar avicularia sometimes occur on 

 other parts of the cell, as represented in the figure (PI. XI. 

 fig. 1). The oooecium is of the usual form, with the charac- 

 teristic group of perforations on the front. 



In the preliminaiy report on the " Biology of the ' Valo- 

 rous' Cruise," printed in the Proceedings of the Royal Society 

 for June 15, 1876, p. 208, Mr. Norman records this form as 

 amongst the Greenland dredgings, and regards it as a new 

 species, which he proposes to name L. Jeffreysii. 



The chief characters wliich he seems to rely upon as 



