HYALOSPHENIA OVALIS. dd 
§ C. Nesetinz. 
1. Hyalosphenia ovalis Wailes. 
(Plate LXII, figs. 3: and 4.) 
Hyalospheniu ovalis 
Wales in Scott. Natur. 1912, pp. 61, 64, fig. 1. 
Test large, pyriform, of a yellow colour, compressed ; 
in broad view the crown semicircular, the sides con- 
verging in slightly concave lines to the aperture; the 
crown perforated with from two to twelve pores with 
beaded internal orifices; the test in narrow side view 
elliptical, truncate, and notched at the aperture; the 
crown and anterior portions of the sides of the test 
furnished, with a wide rounded keel; test in transverse 
section elliptical; aperture elliptical, straight in broad 
view, slightly notched in narrow view ; plasma clear, 
colourless, containing numerous granules and food- 
particles; nucleus large, placed posteriorly, containing 
several nucleoles ; one or two contractile vesicles usually 
present; pseudopodia few, digitate. 
Length 153-177 »; breadth 130-140 w; aperture 
50-55 »; thickness about half the breadth, or less. 
Habitat—Sphagnum. 
Scortanp.—Dumfries. 
Irutanp.—Cahirciveen, Kerry. 
From H. papilio this species is distinguished by its 
much larger size and the keel-like ridge around the 
borders of the test; the number of pores in the crown 
is also usually greater, and the thickening of the test, 
around their inner openings is also characteristic. The 
test is always pyriform in broad view, whilst the test 
of H. papilio is only occasionally so. 
It appears to be rare, for its large size precludes it 
from being easily overlooked. 
