548 Transactions of the Society. 



the interior of spheres, or wliether Brady identified them as pri- 

 mordial cliambers merely on account of their resemblance to the 

 internal shell in fig. 12. If the first alternative is correct, we have 

 definite proof of an alternation of generations between the sphere 

 type and haeusleri. The second alternative would merely prove 

 that Brady was acquainted with the variety haeusleri, but did not 

 separate it from the sphere type. 



Haeusler's remaining species may be quickly dismissed, 

 although we propose to retain the names varietally for taxon-omical 

 reasons. 



Thurammina 2)ainll(^ta var. tubcrosa Haeusler. 



Type, Haeusler (Eef. 21, pi. vi, fig. 24, and pi. vii, figs 6-9). 



Plate XXVIII, figs. 13-16. 



This is merely an aggregation of specimens of an irregular 

 sphere type, and furnished with few papillae. Such specimens do 

 not attain the size and complication of Haeusler's figures in any of 



EXPLANATION OP PLATE XXIX. 

 nae. 

 1-H. — Thurammina papillata var. cariosa Flint. 



Figs. 1. — Youug sphere, showing commencement of reticulated 

 " cavernous layer " of Flint. (Note : The reticulated mark- 

 ings are somewhat diagrammatized.) 

 ,, 2, 3. — Specimens showing development of " cavernous layer " 



obscuring the papillae. 

 ,, 4. — Specimen with minutely vesiculated " cavernous layer." 

 ,, 5. — Specimen with coarsely vesiculated " cavernous layer." 

 ,, 6. — Double specimen, with thick " cavernous layer " obscuring 

 the line of junction between the spheres, and eroded in 

 places. 

 ,, 7. — Triple specimen, with finely vesiculated " cavernous layer " 



completely obscuring the junction of the spheres. 

 ,, 8. — Internal view of specimen, showing reproductive gemmules 



lying within the chitinous membrane. 

 ,, 9. — The same, gemmules more developed. 

 ,, 10. — Aggregation of gemmules removed from test. 

 ,, 11. — Internal view, showing spherules at maximum development 

 filling entire cavity. 

 12-15. — Thurammina papillata var. albicans Brady. 

 Fig. 12.— Typical. 

 ,, 13. — Abnormally large and coarsely papillate. 

 ,, 14. — Coarsely arenaceous specimen. 



,, 15. — Section showing grains of magnetite aggregated in central 

 cavity. 

 16. — Thurammiyia papillata var. haeusleri. Specimen showing four young 



individuals (one laid open) budding from parent test. 

 17. — T. papillata var. castdnea. Specimen showing young individuals budding 



from each side of parent sphere. 

 18. — T. papillata. Sphere type, of chitinous cement construction, enclosing a 

 specimen of Orhulina universa d'Orbigny, which entirely fills central 

 cavity of the Thurammina. 

 19. — T. papillata. Sphere type, very finely arenaceous and without papillae, 



enclosing var. castanea, chitinous form. 

 20. — T. papillata var. castanea. Chitinous specimen, filling cavity of Orbulina 

 universa d'Orbigny. 



All specimens magnified 33 diameters. 



