ADDENDA. 



subject is here alluded to ; but this is not the case : Werner 

 proves, by various phenomena, that a gradual diminution in 

 the waters of the ocean has taken place, but offers no hypo- 

 thesis iii explanation of this fact. 



Prop. 13. " The strata formed by these depositions" (con- 

 stituting the transition rocks of Werner) "were chiefly of 

 rubble-stone, sand-stones: some limestones, breccias, argillite, 

 chert, and perhaps porphyries and sienite." The only transi- 

 tion rocks enumerated by Professor Jameson are transition* 

 limestone, transition-trap, grey-wacke, and flinty-slate ; to 

 which he afterwards adds transition-gypsum. These, I presume, 

 are the only rocks now considered by Werner as belonging to 

 the genuine transition class. Under grey-wacke are placed 

 common grey-wacke (rubble-stone) and grey-wacke slate, some- 

 times confounded with clay-slate (argillite). Professor Jameson 

 himself has, however, considered argillite as a transition rock 

 in some instances. V. Miner, vol. 1. p. 335. &c. 



Prop. 16. Obs. "Hence Werner distinguishes them by 

 the title of stratified rocks/' It should have been, perhaps, 

 fioetz rocks. The terms are, however, frequently used indis- 

 criminately by pupils of the Wernerean school, though by no- 

 means synonymous. 



Page 139. Add to the observation, "we have not ourselves 

 found any variety of baroselenite under an organic form/' 

 Ginelin, indeed, expressly states that terra ponderosce, in 

 which he includes the species just noticed, are never found in 

 an organic form. V. Syst. Nat. T. 111. p. 63. 

 Page 140. Add ff to the words " vegetal petrifactions " (line 12) 

 as a reference to the following Note |f The term vegetable, 

 as generally used in the present study, is certainly incorrect. 

 A vegetable petrifaction or fossil literally implies a petrifaction 

 or fossil capable of vegetation ! We should not, however, have 

 ventured to have proposed a change in a term so long esta- 

 blished, had we not observed, while these sheets were in the 

 printer's hands, such change already adopted, on principles, in 

 our humble opinion, perfectly philological. Vide Desmond' 

 Transl. of Fourcroy's Chem. Phil. Preface, p. xviii. 



