Mr. H. J. Carter on the Fossil Foraminifera of Scinde. 371 



" 3. N. obtusa, Sow." (Ann. Nat. Hist. I.e. pl.7. fig.13).— This 

 has been identified by D'Archiac and Haime (p. 343) with the 

 fossil from Cutch described by Sowerby under this name, chiefly, 

 I presume, from my figure being without "puncta" on the sur- 

 face ; and thus these authors have again been led into error so 

 far as the figure goes ; for in the Nummulite from which it was 

 taken I now find there are abundance of puncta, although in the 

 smaller specimens, from which the description was made, there 

 are only one or two, here and there, attached to the septal lines. 

 Moreover, I find that all the specimens which I now possess, and 

 which respectively come from the valley of Kelat and various 

 parts of Scinde, have that striking character (according to D'Ar- 

 chiac and Haime) which distinguishes all the other Punctulatce, 

 except N. cwrvispira, from N. obtusa, viz. the greatly increasing 

 diameter of the chambers in the direction of, over that across, 

 the spire, towards the margin. In D'Archiac and Haime' s figure 

 of N. obtusa (pi. 6. fig. 136), the chambers, in relative propor- 

 tion, are nearly the same throughout; in which case I have 

 never yet seen a specimen of this Nummulite from Scinde or 

 elsewhere. 



The presence of the puncta, again, or their absence, their 

 attachment to the septal lines or their separation from them, 

 or the existence of both in the same specimen, or indeed the 

 absence of the septal lines altogether and the presence of an 

 abundance of puncta may exist, respectively, in the different 

 forms of the globose Nummulite, N. perforata, which abounds 

 in the valley of Kelat and Scinde, showing that much depend- 

 ence, as I have just stated, must not be placed on the puncta or 

 septal lines for specific distinction. How much the plainness of 

 the puncta, in their white opake form, may depend on the com- 

 pactness of the material of which the fossil is composed, I am 

 ignorant; but it seems to me that the harder and darker it is, 

 the more evident are the puncta, while the lighter and more 

 chalky, the more indistinct, until they disappear altogether. 

 Still, this is not always the case, since in the specimens from 

 Kelat, which are all equally hard, the puncta are sometimes 

 wanting, when the form of the chambers of the central plane 

 proves them otherwise to be of the same species. That all 

 these variations may nevertheless depend on fossilization may 

 easily be conceived, from the puncta in the first instance being 

 the most transparent parts of the test, as shown in Operculina. 

 However, to avoid further confusion, I will now give a more 

 complete description of this Nummulite than I could do formerly, 

 assigning to it the name of N. perforata rather than that of N. 

 obtusa, as I think the former will be found the best adapted 

 for it. 



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