General History of the Marine Polyzoa. 359 
There seem to be two generic types at least* included in 
the group of the Steganoporellide, one of them represented by 
S. magnilabris and the forms which agree with it in the 
structure of the zocecium, the other by such forms as the 
present. For the latter 1 have adopted (provisionally) Jul- 
lien’s name Smittipora, though I am not prepared to accept 
his diagnosis of the genus in all points, and should be dis- 
posed to make it much more comprehensive than he has done. 
The genus Steganoporella (as I propose to limit it) is distin- 
guished by the tubular passage leading from the inner 
chamber towards the external orifice and the corresponding 
modification of the internal orifice (‘ opesta”’ of Jullien), 
which is a simple opening in the calcareous lamina communi- 
cating directly with the inner chamber in Smittipora and 
kindred forms f. 
I at one time referred the present species to Setosel/a, mihi, 
but the British species (S. vulnerata) for which this genus 
was founded does not possess the dithalamic cell. 
The specimens of S. abyssicola from Burmah are crusta- 
ceous in habit. 
Family Microporellide. 
MIcroPoRELLA, Hincks. 
Microporella violacea, Johnston, form plagiopora, Busk. 
(Pl. XIII. fig. 3.) 
Range. Off Tortugas, Florida; France (south-west): Eng- 
lish Coralline and Red Crag, Italian Pliocene. 
Zoecia large, ovate, very regularly placed, punctured or 
areolated round the margin; orifice (primary) arched above, 
lower margin straight ; peristome often much raised, giving 
a tubular character to the orifice; pore subcentral, simple, 
round ; aviculartum originating a little below the orifice, bent 
towards one side of it, and extending obliquely to the margin ; 
mandible slender and finely pointed, curved at the extremity. 
The Burmese specimens agree in all essential particulars 
with Busk’s Crag species. The only peculiarities are the very 
irregular arrangement of the zocecia and the elevated tubular 
peristome which occurs on many of the cells. I see no 
reason for regarding WM. plagiopora as any thing more than a 
slightly modified form of MW. violacea. 
* There are probably more, but I confine my attention at present to the 
two noted above. 
+ See ‘Annals’ for Feb. 1882, “ Contributions towards a General His- 
tory of the Marine Polyzoa.”—IX., pl. v. figs. 8, 9. 
