184 7-] Notice on the Ferruginous Spherules. 711 



principle of generic classification is organic. I assume that every 

 organic variation is a sign of genus ; that nothing but organic variation 

 is a sign of genus ; that we are too ignorant at present of the real 

 nature and use of most organs to decide on their relative value and to 

 reject some because they seem comparatively uninfluential on the 

 habits and economy of the animal endowed with them ; that the organ 

 is always the datum ; its use always the desideratum, and that all or- 

 gans ought to be prominently set forth until their structures, uses and 

 relative importance be decided on ; that all three sorts of teeth are 

 organs, and all therefore are properly introduced to mark genera and 

 even higher groups ; that there is not that entire uniformity of denti- 

 tion among the Ruminants which has been so long asserted ; and, 

 lastly, that the special form of the horns in the Cirvidse, though not 

 strictly an organic mark, may yet be wisely used at present to help the 

 indication of genera^ because it is a very palpable sign, and one besides 

 usually harmonising with, and indicative of other and organic modifica- 

 tions yet partially or wholly understood.* 



Notice on the Ferruginous Spherules imbedded in Sandstone from Lul- 



lutpore, in Bundelcund, by Dr. G. G. Spilsbury.— By H. Pid- 



dington, Curator Museum Economic Geology. 



We have received from Dr. Spilsbury an additional supply of the cu- 

 rious little Ferruginous Spherules described in my report of September 

 1846, from their resemblance in miniature to the spherical volcanic 

 Bombs figured by Mr. Darwin as being possibly volcanic grape-shot, and 

 since that time I have observed that some being sent to the Agricultural 

 Society, Dr. McClelland thought they might be fossil fruits. I have 

 seen these and find them externally the same as ours, and I have there- 

 fore submitted ours to a farther examination, of which the result is — 



That they are infusible before the blowpipe ; that they are not mag- 

 netic, but when exposed to the reducing flame of the blowpipe they 

 become so. That when dissected by long immersion in muriatic acid 

 they leave nothing but a residuum of coarse white granular silex and 



* Mr. Hodgson's correction of an oversight in the description of Genus Axis, page 

 691, reached us after the sheet had been printed off. For " canines in males only," read 

 " canines in both sexes."— Ens. 



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