444 Mr. H. J. Carter on the 



' Traite de Geologie ' of 1883, p. 1027, tlie name of Orhito- 

 lites ManteUi appears among the Alabama fossils. 



With reference to tlie specific value of tlie " conical 

 columns of non-tubular, opaque, white, shellj substance ; " in 

 distinguishing the two types of Orbitoid structure to which I 

 have alluded, I now find that it is by no means so great as I 

 had anticipated ; for while this character appears to be per- 

 sistent in the type of Orhitoides papyracea, it is only partially 

 so in that of OrhitoUtes Mantelli^ seeing that the columns 

 are undoubtedly absent in the Alabama species, in that from 

 Arabia, and that from Burma which I have lately described 

 (* Annals,' 1888, vol. ii. p. 342), but not always so in the speci- 

 mens from Sind. They are undoubtedly absent in the infil- 

 trated specimen from Sind wliichlhave figured in the ' Annals' 

 {I. c), while in the same ferruginous mass of Nummulites from 

 which the latter came there is an umnfiltrated specimen about 

 an inch in diameter in which the " columns " are so undoubt- 

 edly present that, but for the presence also of a portion of 

 the characteristic central plane of this type, I should have 

 set it down as belonging to Orhitoides papijracea. Again, in 

 the specimens of OrhitoUtes ManteUi from Nal, in the pro- 

 vince of Jhalawan, they are not only indicated by the 

 presence of their obtuse ends among the reticulated structure 

 of the surface, but in the section may be seen to have their 

 pointed ends in the intervals between the cells of the central 

 plane. While it will presently be seen that they are equally 

 characteristic of d^Orbigny's Orhitoides media from Maestricht, 

 although they are not represented in his illustrations of this 

 species (l. c), that is if it be the one which it is stated to be 

 in his ' Cours de Geologic ' [l. c). Hence it becomes neces- 

 sary to describe a genuine specimen of Orhitoides media from 

 the Upper Chalk of Maestricht first, and then to compare it 

 with d'Orbigny's illustrations afterwards ; but before entering 

 upon this it is desirable to premise what the references are 

 which appear to justify d'Orbigny's identification, for which 

 purpose the following extract is given from the ' Prodrome,' 

 vol. ii. p. 279, viz. : — 



"Oebitoides, d'Orb. 1847. 



"1349. media, d'Orb. 1847. OrhitoUtes media, d'Ar- 

 chiac, 1837. Mdm. Soc. Gdol. de France, t. ii. p. 178. 

 Faujas de Saint-Fond, pi. xxxiv. figs. 1, 2, 3, 4. Royan 

 (Charente-Inferieure), Lanquais (Dordogne) ; Maestricht." 



Fortunately, through the kindness of Dr. H. Woodward, 



