94 HALKYARD, Fossil Foraminifera of the Blue Marl 



This variety occupies the same position in relation to 

 C. caltrata as C. macrodiscus does to C . rotulata. Under these 

 circumstances it follows that the present form must be reduced 

 from specific to varietal rank. The form is rather rare at 

 Biarritz, but occurs in almost all the Gatherings. 



(There seems no more reason for separating this from 

 C. Cultrata than for separating var. macrodiscus from C. rotu- 

 lata.) 



222. Cristellaria subalata, Reuss. 



Cristellaria subalata, Reuss, 1854, Denkschr. k. Ak. Wiss. 

 vol. VII, (1), p. 68, pi. XXV, fig. 13. 

 Rather rare, but generally typical and well developed. 



(The specimens agree fairly well with the Reuss figures, 

 but the species is not worth separating from C. cultrata 

 (Montfort.) ) 



223. Cristellaria depauperata, Reuss. 



Cristellaria depauperata, Reuss, 1863 (1864), Sitz. k. Ak. Wiss. 



Wien. vol. XLVIII, (1), p. 66, pi. VI, figs. 67-68; and pL 



VIII, fig. 90. 



This species can hardly be called rare as it is present in 

 nearly all Gatherings but those taken at the extreme base of the 

 Marl. From one to four specimens were obtained at each of 

 the other stations. 



(Reuss himself admits the unsatisfactory and variable speci- 

 fic characters of the species. Halkyard's specimens agree on 

 the whole with the description, but morphologically all the 

 specimens might be described as varieties of either C. rotulata 

 or C. cultrata, with few and relatively large chambers."; 



224. Cristellaria budensis (Hantken.) 



PI. VI, fig. 2. 



Robulina budensis, Hantken, 1875, Mitth. Jahib. K. ungar.. 



geol. Anst., p. 58, pi. VII, fig. 1. 

 Robulina budensis, Jones, 1876, Mon. Micr. Journ. vol. XV, 



pi. CXXVIII, fig. 5. 



This variation of the cultrata type has not generally been 

 found in all the material collected. It is frequent in Gathering 

 No. 4 (1893) but very rare in, or absent from, the others. The 

 test is compressed, partially evolute, provided with an umbili- 

 cal boss, and is of delicate growth, with a thin shell-wall. 



