Mr. H. J. Carter on the Fossil Foraminifera of Scinde. 455 



closely allied to Orbitolites in the structure of its horizontal plane 

 (see Dr. Carpenter's sections of Orbitolites in Phil. Trans. /. c.) 

 any more than one can help seeing that Orbitoides dispansa, in 

 the structure of its central plane, is most closely allied to Oyclo- 

 clypeus, Carp. 



Alike, therefore, as Orbitoides dispansa and Orbitolites Mantelli 

 may be in other respects, they are, in the structure of the central 

 or horizontal plane, as strikingly different as Orbitolites and 

 Oycloclypeus. 



For field-service, the absence of the white columns and in- 

 creasing thickness of the horizontal plane towards the circum- 

 ference, as above stated, at once distinguish Orbitolites Mantelli 

 from Orbitoides dispansa. 



Dr. Carpenter (Phil. Trans. 1856, p. 195, foot-note) states 

 that I have fallen into an error, which has been corrected by 

 D'Archiac and Haime (p. 349), in placing what M. d'Archiac 

 considered before as " Orbitolites " under the head of Orbitoides 

 dispansa and Orbitoides Fortisi seu Prattii, with reference, I 

 suppose, to my having changed the name of the fossil first de- 

 scribed from " Orbitoides Mantelli" to " Orbitolites Mantelli." 



I have, however, just stated that Orbitoides dispansa and Or- 

 bitoides Fortisi seu Prattii are the same, and have always done 

 so. That Orbitoides Mantelli, D'Orb., is very different, 1 have 

 also shown ; but I question, now that Dr. Carpenter has so 

 clearly defined Orbitolites, whether Orbitoides Mantelli ought to 

 retain the name under which I have described it, any more 

 than Orbitoides dispansa should be called " Cycloclypeus dis- 

 pansus." I think it had better even have retained the old name 

 of Orbitoides Mantelli, D'Orb. But it must be plain now, 

 that if Orbitoides dispansa is to be considered the type of the 

 genus, our Orbitoides Mantelli, D'Orb., is not of this type, and 

 therefore should still have another name. It has already had 

 three, viz. 1. Nummulites Mantelli, D'Orb. ; 2, Orbitoides Man- 

 telli, D'Orb.; and 3, Orbitolites Mantelli, Cart. 



Propayative spherules. — I have observed these bodies in some 

 of the cells of the infiltrated specimens of Orbitolites Mantelli, 

 but they are not numerous ; and it is only here and there that 

 I have been able to observe them in the specimens of Nummulites 

 subbxvigata, with which they are imbedded ; while the imperfect 

 infiltration of the whole, compared with the specimens of Orbi- 

 toides dispansa, &c, from Wasna, in which these " spherules " 

 abound, seems to indicate that the former were imbedded long 

 after death, while the latter must have been imbedded almost 

 alive. 



"2. Orbitolites ?" (Ann. Nat. Hist. I. c. p. 175, pi. vii. 



figs. 40, 41). — The specimen thus noted and alluded to by D'Arch. 



