394 Professors King and Rowney on 



" nummuline layers" having resulted from pseudopodial tubu- 

 lation*. 



lOtli. The so-called " stolons " and " passages of communi- 

 cation exactly corresponding with those described in Cyclo- 

 clypeus^^ (fig. 2, h h) have been shown to be tabular crystals 

 and variously formed bodies belonging to different silacid 

 minerals, wedged crossM'ays or obliquely in the calcitic inter- 

 spaces between the grains and plates of serpentine f- 



11th. The " canal-system " is composed of serpentine, mala- 

 colite, and other silacid minerals. Its typical kinds in serpen- 

 tine may be traced in all stages of formation out of plates, 

 prisms, and other solids undergoing a process of superficial 

 decretion J. In malacolite &c. they are made up of crystals 

 (single or aggregated together) that have had their planes, 

 angles, and edges rounded ofi:', or have become further reduced 

 by some solvent. 



12th. The " canal-system," in its remarkable branching 

 varieties, is completely paralleled by crystalline configura- 

 tions in the coccolite marble of Aker, in Sweden, in the cre- 

 vices of a crystal of spinel imbedded in a calcitic matiix from 

 Amity, New York, and in a gemmiferous calcitic rock occur- 

 ring in Ceylon §. 



13th. The configurations^ presumed to represent the " canal- 

 system," are totally without any regularity in their form, rela- 

 tive size, or arrangement ; and they occur independently of, 

 and apart from, other " eozoonal features " (Amity, Boden, 

 &c.), — facts not only demonstrating them to be purely mineral 



* Ibul, vol. xxii. p. 191 ; Proc. Royal Irish Academy, vol. x. p. 517. 



t Quarterly Journal Geological Society, yol. xxii. pi. xiv. figs. 10 & 11, 

 pi. xy. fig. 15, pp. 207 & 208. 



X Proc. Roy. Msh Acad. vol. x. pi. xliii. figs. 7 & 8, pp. 527 & 528. 

 Speaking of the " arborescent structui-e " of the " canal-system," Dr. 

 Carpenter assumes that we "maintain it to consist of mere mineral bifil- 

 tratiotis " ! And hence, by adopting the following mode of reasoning, he 

 evidently feels that a decisive case has been made out against us. As 

 the " ramifications pass across the planes of cleavage, every mineralogist 

 will at once say that this is perfectly conclusive — against their being, by 

 any probability, mere inorganic infiltration ; that nothing but organic 

 structures could in this manner prodvice a ramification of one mineral in 

 the interior of another, a ramification of sei-pentine in the interior of car- 

 bonate of lime passing against its crystalline planes " (' Pharmaceutical 

 Journal/ Feb. 11, 1871, p. 649). If this vrere the case, it would necessa- 

 rily foUow that imbedded minerals which produce " ramifications " in the 

 " interior of calcite and passing against its ciystalline planes " (as is com- 

 mon with native silver, prismatic pyrites, glauconite arborescences in 

 calcite or the so-called Hislopite, the latter as made known by Mr. Cai-ter) 

 can be " nothing but organic structures " ! It is to be regretted that Dr. 

 Carpenter still makes use of this argument in his last communication. 



§ Geological Magazine, January 1873. We have lately detected typical 

 " canal system " in a choudrodite rock from the United States. 



