Polyzoa of Queen Charlotte Islands. 469 
Membranipora minuscula, n. sp. (Pl. XX. figs. 8, 3.a.). 
Zoecia small, oval, arranged in quincunx (somewhat irre- 
gularly) ; margin a good deal raised, thin, smooth, no spines ; 
on an oblong area, placed above the cell, occasionally a small 
circular avicularium, slightly raised, the mandible directed 
upwards. Ogciuwm semicircular, shallow, just covering the 
extremity of the cell, smooth, with a subcircular membranous 
space at the back (? avicularian). Zoarium forming a thin 
flat crust, usually of small size. 
Loc. Houston Stewart Channel, &c., common. 
Membranipora membranacea, Linneus. 
Queen Charlotte Islands, incrusting the stem of a sea-weed. 
The only specimen that occurs is covered with numerous 
tall, very stout, membranous processes, which occupy the place 
of one of the spines at the top of the zocecium. They are 
smooth and glossy, narrow at the base, somewhat enlarged 
about the middle, and taper off to a point above. They are 
no doubt modified spines; but we have no clue to their his- 
tory. They must not be confounded with the processes on 
the so-called “ tower-cells,” which originate on the membra- 
nous front wall of the zocecium ; both are probably abnormal 
growths with no special function. 
(Norway, Britain, Brittany, Adriatic; New Zealand, Aus- 
tralia. ] 
Membranipora membranacea, form serrata. 
Zoecia rectangular-oblong, greatly elongated; margins 
smooth ; at the top of the cell, on each side, a short blunt spine ; 
round the inner margin a narrow crenated border. 
Loc. Virago Sound, spreading over the surface of a sea- 
weed. 
This is a remarkably pretty variety, and presents a very 
distinctive appearance. ‘The cells are of unusual length, and 
exhibit great regularity both of form and arrangement. But 
the character which distinguishes it most and gives it a very 
marked individuality is the narrow crenate edging which 
fringes the inner margin of the cell. The crenulations are 
small and close-set and for the most part regular; here and 
there Jonger spinous processes rise amongst them and project 
over the area. One of these is always placed in the centre of 
the lower margin of the cell. 
