﻿164 PEOF. T. G. BONNET ON ANTIGOEITE [^laV IQoS, 



(9433 feet), with a precipitous eastern face, uj) which a narrow path 

 leads obliquely from the Fee Alp. The whole, so far as I could see,^ 

 is serpentine, rather fissile where first traversed, but afterwards 

 generally massive. This is of the usual rather dull-green colour, 

 mottled with darker patches (the fissile specimens being of a paler 

 tint, DO doubt from incipient weathering), and the exposed surfaces 

 are changed to a fawn-brown colour. In fact, the blocks so 

 abundant in the moraines of the Fee Glacier, specimens of which 

 were described in 1905, represent either this mass or some part of 

 the Allalinhorn (13,235 feet) of which it may be a spur. The 

 rock is considerably harder and tougher than the ordinary bastite- 

 serpentine, and as the surface is everywhere rounded by ice-action, 

 it is difficult to obtain well-shaped specimens. I took samples : — 

 (1) at the spot where I turned back (probably about 200 feet below 

 the highest point) ; (2) from about half-way between this and the 

 place where the path reaches the top of the cliflP ; and (3) from the 

 fissile part, near its base. 



The first (I) consists of the following minerals: — antigorite in 

 rather irregularly matted flakes, seldom exceeding -005 inch in 

 diameter — those in one or two little patches being distinctly smaller 

 than the rest. A few minute granules giving bright polarization- 

 tints may be residual augite, but occasionally bear some resemblance 

 to talc. One or two grains of fair size and irregular outline, of a 

 very pale warm -brown tint, show a close parallel cleavage, ex- 

 tinguishing parallel to it with crossed nicols and giving in other 

 positions a dull but rich blue colour ; flakes of antigorite sometimes 

 pierce these grains, sometimes lie between their cleavage-surfaces. 

 A mineral presenting a resemblance to this occurs in one of the 

 Anglesey serpentines," where I think that it represents a member of 

 the enstatite-group. The second (2) consists of a similar antigorite, 

 but with some residual augite, pierced and often ' riddled ' by flakes 

 of the other mineral, which, to judge from the polarization-tints, 

 may have formed grains about O'l inch in diameter. Granules of 

 iron-oxide and sulphide are rather numerous, but irregularly 

 distributed, being often apparently associated with the augite and 

 probably showing signs of crushing. The third, not the most fissile 

 variety of (3), consists of antigorite and iron-oxide (hardly any 

 sulphide) as above : both exhibiting a more definite foliation, and 

 the latter occurring in more distinct layers, which suggest here 

 and there the crushing-out of grains, and sometimes impart a 

 brown stain to the neighbouring serpentine. ]S"o residual augite is 

 visible. 



It is rather remarkable that none of the specimens prepared 

 either for this or for our former paper contain any residual 



^ Want of time obliged me to turn back near the foot of the rocky mound at 

 the upper end. 



- That from near a quarry south of Cru-Gla?, Quart. Jouru. Greol. Soc. 

 vol. xxxvii (1881) p. 45. 



