Tkuramniina papillata Brady : a Study in Variation. 551 



^' Goldseeker " dredgings, where it attains a size considerably 

 greater than Brady records. It appears to be a distinctive form, 

 having little connexion with the typical papillata, but in rare 

 instances hardly separable from cariosa. The papillse, when flush 

 with the surface of the test, as they often are, and covered witli a 

 loose sandy coat, cannot be distinguished from the outside, but a 

 section will generally reveal a few dimpled pits in the inner wall 

 which mark the position of the superficial papillse. The papillae are 

 very few in number, and in some instances perhaps entirely lacking, 

 in which case the form would be indistinguishable from Stortho- 

 sphsera, to which it is possibly nearly allied. 



A curious feature observed in connexion with albicans is worth 

 recor'ling. The variety appears to have a curious dislike for 

 magnetite. Several specimens which we have laid open contained 

 a number of minute grains of magnetite aggregated in the cavity 

 (PI. XXIX, fig. 15), the grains having evidently been rejected from 

 the sand collected for the construction of its thick-walled test. 

 This habit may serve to account for the abnormal whiteness of the 

 test of albicans as compared with the other varieties. We have 

 observed the same practice in Storthosph^ra. 



Thurammina papillata var. sordida var. nov. 

 Plate XXX, figs. 1-6. 



"We propose this varietal name for a very characteristic form 

 which occurs frequently in several "Goldseeker" gatherings, and 

 which is very distinctive in appearance. 



Test free, spherical or irregularly spherical in shape, colour 

 ranging from nearly white to dark brown, slate, or nearly black. 

 Surface rough, and usually coated with finely adherent mud, but 

 specimens have been seen without any muddy layer on the brown 

 chitin sphere. These chitinous specimens have a crinkly surface, 

 and are sometimes covered with very minute papillse. Interior of 

 the sphere lined with a brown chitinous membrane which is 

 apparently in several layers. The wall of the test appears to 

 consist of a series of chitinous layers alternating with mud incor- 

 porated with chitin. No papillse visible externally as a rule, but 

 papillar depressions are occasionally visible in sectionized tests. 

 The exterior of the sphere is always very wrinkled and dirty in 

 appearance, and frequently has wliat appears to be sub-chitinous 

 muddy t reads, or perhaps dried protoplasmic extrusions, irregularly 

 projecting from it. The colour of var. sordida is evidently depend- 

 ent on the nature of its environment, specimens from Haul 228 

 (1600 metres, Globigerina ooze) being nearly white, and ha vino- 

 minute Glubigermee attached to the surface layer of mud, while 

 those from Haul 198 (1236 metres, dark brown mud and sand) are 

 very dark in colour. 



The central cavity is generally more or less filled with a dried 



