190 Mr. H. J. Carter on " Eozoon canadense." 



panying copy of my paper on the " Form and Structure of 

 Operculina arabica^'' read before the Bombay Branch of the 

 Boyal Asiatic Society so far back as May 1852, and pub- 

 lished in their Journal and in the ' Annals and Magazine of 

 Natural History ' of the followiug year, together with many 

 other papers subsequently published in the latter, from time 

 to time, on the structure and adult forms of several fossilized 

 Foraminifera, including new species. You may also thus 

 fully understand how grateful I feel to you for having been 

 the first to send me a specimen of the Laurentian rock, and 

 to bring the subject of its structure and composition before me 

 under the mineralogical point of view detailed in the papers 

 published conjointly by yourself and Prof. RowneVj to which 

 I have alluded. 



You will also observe, by the figures in the plate attached 

 to my paper on Operculina^ that, at a very early period, I 

 demonstrated the system of foraminiferous structure in a recent 

 Operculina and identified it with the structure of a fossil Num- 

 mulite. How much more completely than others, a comparison 

 of our descriptions and illustrations respectively will show, it 

 not being my business here to lay claim to any thing beyond 

 a position to be able to compare genuine foraminiferous struc- 

 ture, both living and fossilized, with the so-called Eozoon cana- 

 dense. 



Previously, however, to stating my observations in this 

 respect, I would say a word or two on the law of form in 

 organized beings ; for this bears upon the subject. 



That the " law " exists in the mineralogical as well 

 as in the organic kingdom may be seen in the common 

 mineral growth temied " dendrites." But, besides this 

 familiar example, it may be observed in what are called 

 "moss-agates," coming from the geodes of trap — that is, 

 from a volcanic rock. Of the latter I possess a polished and 

 mounted specimen, composed of opalescent chalcedony, in 

 which there is a growth oi fflauconite that, when viewed under 

 an inch compound power, would, by any one not acquainted 

 with the geological facts, be termed a " branched Conferva." 



Again, I possess a similarly polished and mounted specimen 

 of green calcspar (that designated by Prof. Haughton " Hislo- 

 pite "), also from a trappean geode of Western India, in which 

 there is a growth of glauconite so like the remains of dead 

 incrusted Conferva from a dirty pond that, without being 

 acquainted with its geological position, this would also be pro- 

 nounced to be Conferva in such a state fossilized. 



So far the " law of form " is the same in both kingdoms, 

 and hence the necessity of knowing this before we state confi- 



