the Nomenclature of the Foraminifera. 299 



{8. pulcheUa) in 1839. In 1866 Reiiss published the name 

 HeterostomeUa as distinctive of the Textilarian Sagraina 

 (Sitzungsb. Akad. Wien, vol. lii.). Ehrenberg's '■'■ Loxosto- 

 murnj'' though older (1854), is so misapplied by him {to Poly - 

 morphina, Vulvulina, and a transitional form between the 

 latter and Textilaria proper) that naturalists may well hesitate 

 to use it. HeterostomeUa aculeata is figured also in pi. xxvii. 

 figs. 21, 22. 



Fig. 27, Polymorphina tiirio^ is a narrow and typical speci- 

 men of VirguUna Schreihersn^ Czjzek, which is subgenerically 

 related to BuUmina. Figs. 28 & 29, Pleurites'} calciparus^ 

 30, Sphceroidina cretacea, and 32, Orammobotrys anglica^ are 

 broad and flattish individuals of VirguUna Hemp>richn (Eihx.). 

 This species is well figured (under many different names) in 

 the ' Mikrogeologie.' It is very variable in form, but constant 

 in the cloudy, or seemingly muddy, opacity of its shell — a 

 structure beautifully engraved in pi. xxix. fig. 38, and else- 

 where. This species is very common in the Indian seas, with 

 its misty, dull shell, of variable growth, sometimes regularly 

 Virguline, with alternate chambers, sometimes passing into 

 BuUmina proper, sometimes short and nearly round, like Cas- 

 sidulina and in other subvarietal shapes. It is the only Vir- 

 guUna that takes on a sandy condition, becoming subarena- 

 ceous, and thereby very delicately rugose. Ehrenberg appears 

 to have first noticed it in the Tertiary Limestone from Thebes, 

 Egypt. In pi. xxiv., illustrating the Foraminifera from that 

 rich rock, he gives the name 8trophoconus Jlemprichii to a 

 fine complanate specimen (fig. 32) ; some smaller individuals 

 (figs. 29, 30, 31) he puts under the same genus, and another 

 as " Textilaria'^ or Orammobotrys.'''' His " HtrophoconV are 

 all either Virgulinre or Bulinmue ; therefore the name is not 

 required. Other instances of VirguUna Heniprichii (fossil) 

 occur at pi. xix. fig. 86 (?) , ^gina ; xxi. fig. 88, Oran ; xxiii. 

 fig. 19, Mokattam ; xxv. fig. 15 (?), Antilibanon; xxvi. figs. 

 19-24, 26, 27, Cattolica; xxix. figs. 32-36, Moen Chalk; 

 XXX. figs. 18, 19, 21, Eugen Chalk ; xxxii. ii. figs, 18, 20, 

 Mississippi Chalk; xxxiii. xiii. fig. 27 (?), San Francisco. 

 Of these some are remarkable ; for instance, the Vaginulina ? 

 paradoxa and V. ohscura (pi. xxvi. figs. 26, 27) are nearly cy- 

 lindrical and subarcuate, such as occur in the Jurassic Clays, 

 in the Gault, and in the Chalk * ; they arc old " Secondary " 

 Virgulime. A variety (pi. xxx. fig. 18), termed ^^Polymor- 

 phina nucleus,^^ shows a passage into Cassidulina. An out- 



* Such a Vin/ulina from the English Chalk is figured in Elev's ' Geo- 

 logy in the Garden,' IS59, pi. 2. fig. 12, and pi. 8. fig. 12 c; p. 195 Sec. 



21* 



