a neio Sjjecies of Foramwifera. 313 



new, and that therefore he who examines most will, ccetens 

 paribus^ be able to describe the object most correctly. 



Although I have often sought for the pseudopodial pro- 

 longations of the sarcode from the aperture of Squamulina 

 scapula when in sea-water and in a living state and appa- 

 rently under favourable circumstances as regards rest &c., 

 yet I have never been able to see them. But it should be 

 remembered that they could only be viewed as opaque objects 

 by reflected light, Avith, at the nearest, only ^-inch compound 

 power, while in general these prolongations can only be just 

 seen by transmitted light Avith 5-inch, and then only under 

 the most favourable circumstances as regards fresh sea-water, 

 undiminished vitality, and with little or no molestation — a 

 coincidence of conditions so difficult to obtain that I could 

 hardly expect, with the power first mentioned, to be suc- 

 cessful. 



What, however, I could not obtain in this way while the 

 animal was entire, I have managed to get by dissection while 

 fresh ; and thus all but seeing the animal substance move has 

 been revealed by the processes just mentioned, under which 

 the necessary magnify ing-power with transmitted light could 

 be used with impunity. 



By tearing the test to pieces, its composition can be easily 

 ascertained ; and, first, we find that it is for the most part 

 composed of colourless hyaline grains of quartz and sponge- 

 spicules, sometimes one preponderating, sometimes the other, 

 the former being so small that they look like pounded glass, 

 and, being all colourless, give the test its white appearance ; 

 while the latter, which may be entire or fragmentary to an 

 equal degree of minuteness, are derived indiscriminately 

 from all kinds of sponges of the locality, calcareous as well 

 as siliceous. They are chiefly fragmentary about the lower 

 extremity, where they are tessellately connected by chitinous 

 substance exactly like the arenaceous particles on the tests of 

 some Diffiugice^ and equally heterogeneous, although, like 

 many Diffiugice^ there is evidently a preference here for par- 

 ticular objects, and especially for transparent substances 

 without colour, inasmuch as, although nearly every thing else 

 of the kind in the locality (that is, having recourse to foreign 

 objects for the construction of its habitation) partakes of the 

 ferruginous red material (argil and quartz) that, from the con- 

 tact of the waves with the cliffs of the New Red Sandstone 

 series here, deeply and continually tinges the sea, the animal 

 of SquaniuUna scapula rejects all but the absolutely colourless 

 grains : hence it is always pure white. 



Further up the column the fragments of the spicules are 



