.and exliibit in peripheral outline as many facets and angles a.s- 

 there are segments in outer whoi-1. External surface smooth. 

 Aperture small, terminal, obscure. Length, ^^^ in. 



The species now described is distinguished from its congeners 

 by the great number of its cliambers, their shallowness in com- 

 parison with their length, and the completeness of their investing 

 character. Its nearest analogue in the Milioline series apj)ears to 

 be 21. ah-eoJiniformis, Br. The latter species can be easily dis- 

 tinguished by its arenaceous test, tubular chambers, and deeply 

 depressed sutures, whilst M. migularis is always porcellaneous in 

 its testaceous investment, the chambers are compressed trans- 

 versely to little more than narrow slits, and the sutures are 

 flush or marked by prominent angles in peripheral outline. Lower 

 Bed, moderately common. 



22. t J/, secans, d'Orb. Upper Bed, rather scarce. 



23. fM. hicornis, W, and J. L'pper Bed, very rare. 



24. fJ/. insignis, Brady. Upper Bed, very rare. 



Genus — Spiroloculixa, cVOrhigny. 



25. *>S'. asperuhi, Kar. Rather coarsely arenaceous, with a 

 thin outspread test. In the Muddy Creek si^ecimens none but 

 the marginal segments are distinctly visible on the exterior. 

 Lower Bed, rare. 



26. ;S'. grata, Terq. Lower Bed, rather scarce. L^pper Bed, 

 very rare. 



27. */S'. a,Jfixa, Terq. Lower Bed, ratlier scarce. 



28. jS. limbata, d'Orb. Uf)per Bed, rather scarce. 



29. ^S. Tateaua, sp. nov. PI. i., tigs. 4, 5. 



Test oblong or nearly circular, much compressed ; primordial 

 region biconvex and fusiform, consisting of numerous elongated 

 segments arranged in an acervuline manner. Later chambers 

 (varying from three to six on either side) flattened, outspread, 

 and arranged concentrically. Segments narrow, smooth, nearly 

 flush, much attenuated near the raised centre, increasiiig 

 gradually in diameter towards the outer margin. Periphery 

 rounded. Average size, -^\j in. diameter. 



This shell is constructed on a double plan of growth, the earlier 

 portions being Milioline, or investing, and the latter segments 

 outspread or Spiroloculine. The acervuline chambers often 

 exhibit a close resemblance to small examples of Jfiliolina 

 pygmrm, and when the outspread portion of the test is reduced to 

 a single segment on either side, as is the case with some speci- 

 mens, the analogy is very close. The outer chambers form a 

 fringe around the thickened centre very much like the ahe of 

 certain seeds. It is a small and delicate shell, the outspread por- 

 tion being sufiiciently translucent to show by transmitted light 



