HYALOSPHKN1A OVALIS. 55 



C. NEBELINJE. 



1. Hyalosphenia ovalis Wailes. 

 (Plate LXII, figs. 3 and 4.) 



Hyalospheniu ovalis 

 WAILES 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 /A; aperture 

 50-55 p. ; thickness about half the breadth, or less. 



Habitat. Sphagnum. 



SCOTLAND. Dumfries. 

 IKKLAND. 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. 



