394 THE CANADIAN NATURALIST. [Vol. X. 



older cells, arched above, slightly contracted a short way above 

 the lower margin, which is a little curved outward: peristome 

 not raised, the inner edge of the oral aperture finely denticulate; 

 3 or 4: spines above; on each side, in a line with the lower 

 margin, a strong nodulous process; about the centre of the 

 margin an ((viadanum, with rounded mandible placed on a 

 swelling, which extends some way below the mouth, and facing 

 sideways, mandible directed upwards ; often on the front of the 

 cell near the bottom (to-wards one side) a bracket-like projec- 

 tion, bearing a rounded aviatlarliim. Ocecium (?). 



Zooriimi forming a brownish patch on shell. 



Loc. Houston-Stewart Channel, Queen Charlotte Islands (7)r. 

 6r. M. Dawson). 



LEPRALIA CLAVICULATA, N. SP. 



Zooecla ovate or lozenge-shaped (sometimes irregular in shape 

 and size), quincuncial, depressed ; surface glossy, thickly covered 

 with minute circular punctures, which give it a pretty speckled 

 appearance ; orifice arched and expanded above, slightly narrowed 

 below, contracted by small projection on each side a short dist- 

 ance above the lower margin, which curves slightly outward. 

 Avicularla keyhole shaped, placed on a distinct area very much 

 smaller than that of the cell, and commonly immediately above a 

 zooecium, mandible directed upward. Ooeciwn very large, elon- 

 gate (much higher than broad), depressed toward the opening, 

 rising above into a kind of knob, white, glossy, thickly punc- 

 tured : the surface for some distance above the oral arch fre- 

 <|uently traversed by longitudinal furrows. 



Zoariimi a large, spreading crust. 



Loc. Houston-Stewart Channel, Queen Charlotte Islands (^Dr. 

 G. M. DciKSon^. 



MucRONELLA, Hincks. 



MUCRONELLA PR^LUCIDA, N. SP. 



Zocecia ovate quincuncial, slightly convex, separated by raised 

 lines, surface thickly covered with roundish punctures, lustrous; 

 orifice arched above, lower margin straight (no denticles) ; peri- 

 stome raised, especially at the back or in front, where it rises in 

 the centre into a blunt mucrouate projection, which bends slightly 

 inwards, the surface of the peristome smooth, entire, and very 

 glossy. Avicularla none. Ooccium (?). 



Loc. Houston-Stew^art Channel, Queen Charlotte Islands (^Dr. 

 G. 31. Dawson). 



