16 FieELD CoLUMBIAN MusEuM— GEo.oey, VoL. III. 
or more component lamelle joined end to end. The ends 
of these component lamellze are usually rounded. The lamelle 
are frequently crossed by fractures which usually run normal to 
the length, but are occasionally more inclined. 
Between*chondri with a structure of the above character and 
those which are porphyritic there seem to be all gradations. The 
stages are: 1. Chondri in which the lamellae are wider and fewer in 
number; and 2. Wide lamellae extending only partially across the 
chondrus. If the writer is correct in this observation, it is easy to 
see that differences of extinction do not necessarily prove a poly- 
somatic origin for a chondrus. ‘The lamelle of each chondrus of the 
types figured above are doubtless of a single generation, though 
differently oriented. So the crystals of a single chondrus though 
differently oriented may be of a single generation. Another arrange- 
ment of chrysolite and glass lamella which was seen in addition 
to those noted above was an eccentrically radial one. ‘These la- 
melle are wider than those which are parallel. In this case the 
lamelle are wedge-shaped, and are enclosed in a glass so dark 
as to be opaque. Inthe porphyritic chrysolite chondri the crystals 
were for the most part uniform in size. In one chondrus, however, 
a large crystal with rectangular outline was seen to occupy the 
center with smaller ones grouped concentrically about it. In another 
large chondrus a smaller one was enclosed. In addition to its 
occurrence in chondri chrysolite is to be found in individual crystals 
scattered through the mass of the meteorite. These crystals usually 
do not appear tobe formed in place, but to be fragments consolidated 
with the chondri. They show no signs of decomposition or wear, and 
are free from inclusions. In outline they are rectangular to polygonal, 
and in length measure from .2 to .5 mm. 
The enstatite chondri show little variation from the usual fan- 
shaped forms. The individual fibers in these forms, however, are 
usually much less distinct than the individual lamelle of the chrys- 
olite chondri. In one enstatite chondrus an appearance of a system 
of fibers crossing the main system at right angles was found on 
study with a higher power to be due to a textural change across 
the fibers along these lines. Such a change suggests strain. Large 
individual crystals of enstatite occur, the largest noted being 
lath-shaped and having a length of 4 mm. anda width of 2 mm. 
This is truly a remarkable size when compared with that of the 
general constituents of the meteorite. The outlines of this crystal 
were irregular, yet it was sharply separated from the surround- 
