Notice of the Address of T. Sterry Hunt. 91 
8. That he cites Naumann as sustaining the “theory of envel- 
opment :”—when this learned crystallographer and mineralogist 
has only commended Delesse’s chapter on the envelopment of 
minerals in crystals, and presents in his Mineralogy (the last 
edition of which, that of 1871, is now before me) the subject of 
pseudomorphism in the usual way, with nothing whatever on the 
theory of envelopment ; and, under the-description of the species 
serpentine, he speaks of “large pseudomorphous crystals o 
serpentine from Snarum which still contain a nucleus of un- 
altered chrysolite.” 
There is hence no foundation for Mr. Hunt’s statement that 
his views are “ably supported by Delesse,” or any occasion for 
the ‘‘no small pleasure ” he derived from Naumann’s letter; or 
any warrant for the remark (p. 47) that Delesse and Naumann 
hold the “view ” “that the so-called cases of pseudomorphism, 
on which the theory of metamorphism by alteration has been 
built, are, for the most part, examples of association and en- 
velopment, and the result of a contemporaneous and original 
crystallization.” These men of science are not to be counted 
friends, it has not been their fault, as they have always stats 
Be yt 
announced opponents, with one or two exceptions, hold the 
views which Prof. Hunt has attributed to them in his address. 
We are glad to know that this is not the usual American: 
method of dealing with authorities. 
9. That while setting down the Taconic rocks, and rightly, 
as Lower Silurian in age, he denominates the micaceous gneisses, 
diorites, epidotic and chloritic, steatitic and serpentinous rocks, 
talcoid mica schists, quartzites, and clay-slates (which are always 
without staurolite or andalusite), in fact, the whole range of 
metamorphic rocks, with small exceptions, between the Connec- 
ticut river and the great limestone formation of the Green Moun- 
tains (admitted to be Lower Silurian), as the Green Mountain 
es, and makes the whole “pre-Cambrian” in ag 
ug 
ere are gneisses, mica schists, and chloritic taleoid (or mica) 
schists in the Masoud series, and therefore of admitted Lower 
