1883.] 427 [Wadsworth. 



The three numbers in my earlier paper, which Dr. Merrill quotes 

 as numbers of rocks (M. 455) are the numbers of three chemical 

 analyses (B. 286) given by Mr. King ! Again with all the com- 

 plaint made that I gave no numbers in my abstract, it has been 

 entirely overlooked that I gave data therein whereby my entire 

 disagreement with some 140 different specimens as determined 

 by Zirkel, and the numbers thereof could be readily ascertained. 



Dr. Merrill's statements about the diorites do not, except in a 

 few points, concern me ; since I believe that the rocks called by 

 that name are in every case, or nearly so, varieties of other spec- 

 ies and generally produced by alteration. 



The Kawsoh " diorite " (M.457 ; W. 257), in which I found au- 

 gite, had the augite well marked, but since Dr. Merrill could only 

 find epidote in the section examined by him and since he states 

 among other points that " quartz is pretty abundant in it, while Zir- 

 kel said it contained almost none, and also because Merrill's descrip- 

 tion does not at all accord with my language it is fair to presume 

 that he had a different rock. It is possible he may be mistaken 

 in his epidote, for that mineral occurs in such rocks not in frag- 

 ments but as an alteration product. Where Dr. Merrill writes 

 of No. 187 that it is " a very simple though beautiful diorite, it 

 is moreover a pretty fresh rock " (M. 458), and I find in my notes 

 written with the rock in my hand in 1878 that " the hand speci- 

 men is so weathered and dirty I can make nothing out of it," it 

 would certainly seem that we are not discussing the same rock. 

 I certainly found quartz and mica in the number 1389 of the year 

 1878. (W. 258 ; M. 459). 



The same change in hand specimens and sections, if Dr. Merrill 

 is correct in his statements, will probably account for Nos. 164, 

 167 and many others. 



Concerning No. 77 (M. 460 ; W. 256) it is proper to assure Dr. 

 Merrill that in 1878 no hand specimens in the collection bore 

 numbers, therefore his informant is mistaken in the statement 

 that it bore the No. 1488. Furthermore, I have already stated 

 that I called attention " by writing [in pencil] upon the labels to 

 certain errors in slides and to the misplacement of the hand spec- 

 mens " fW. 273), and it is natural that these errors should have 

 been corrected before he made his examination. If there is a 

 " general similarity easily recognizable between the section and 



