322 Mr. II. .1. Carter on Squamuliiia varians, 



matter, I should have said it was one and tlic same. The 

 arenaceous cliaracter of tlie test, however, makes the difference, 

 if not also its pseudo-septal prolongations into tlie interior of 

 the chamber. Schultze's calcareous forni, which also appears 

 to be much more minute, I have not seen. 



S. ran'anf! closely resembles in every way the plano-convex 

 portion or pedestal of the foregoing species ; we have oidy to 

 take away the columnar portion of S. scojnda to have the more 

 simple form of it which appears in S. varians when the a})er- 

 ture is in the summit, and the base internally denticulated. 



Like the plano-convex portion of S. scopnia, also, it varies 

 much in its circumferential outline, as it does in the amount 

 and extent of its pseudo-septal radiate prolongations internally, 

 being sometimes without any of the latter, and thus presenting 

 a simple single chamber (hg. 1) ; while at others it is more or 

 less crenulated throughout by the inward denticulatious of the 

 test, approaching the many-chambered form of the nautiloid 

 Foraminifera (fig. 4). 



It also varies very much in shape and size (compare fig. 1 

 with fig. 5), but is always characterized by snow-Avhiteness, 

 from the minutely comminuted state of the colourless grains 

 of quartz of which the test is composed — thus resembling in 

 this respect, like S. scopuJa^ the whiteness of powdered glass. 



Sometimes pointed and capitate portions respectively of pin- 

 like spicules are observed to be present, and to project some 

 distance beyond the surface of the test (fig. 1), still further 

 allying it in this respect to S. scopidn. 



There do not appear to be any pores about the surface, and 

 only one large aperture, which varies in position, as above 

 stated, being most conspicuous when on the summit or side of 

 the test. 



Occasionally light yellow spots are seen on the test; but this 

 is where the chitinous substance is devoid of the arenaceous 

 material. 



The internal contents are also above noticed. It seems to 

 feed mostly on Melosira, as there is hardly a specimen which 

 does not contain the disks, both singly and in filament, of this 

 Diatomacean. 



Besides, occasionally I found a number of granulated plastic 

 cells, which appeared to me to be a stage in advance towards 

 development of the spherical nucleated reproductive ones (other- 

 wise absent), wliich might thus be born in the state oi Amfvha'. 

 Analogy favours this view. 



As with S. scapula^ one cannot help seeing, in the smooth 

 tessellated te.st, composed especially of quartz-grains &c., a 

 resemblance to the tests of Diffltu/in — and in the selection of 



