102 Scientific Proceedings, Royal Dublin Society. 
the fine linear opaque streaks, which seem to be fluidal in origin, 
run through them undisturbed ; the structure of the spherulites 
has also, in some cases, survived epidotization. ‘The varioles not 
only become confluent, but in some cases a larger entirely includes 
a smaller one. The structure of the varioles is rendered very 
obvious by the presence of opaque white or brown material similar 
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ANS GI. dines. ~~ 7. 
Fic. 3.—Variolitic structure. G. altered glass, E. Epidote, crossed by cracks filled 
with calcite (chris-crossed). Magnified about 12 diameters." 
to that previously alluded to as occurring in the axis of the felspar 
crystals of the spilite. This borders the rays of felspar, which 
now chiefly constitute the variole, so that their course may be 
traced without the aid of polarized light (fig. 4); occasionally, 
however, it is developed to superabundance, and only serves to 
obscure: the same material occurs as a definite border about the 
periphery of the varioles; sometimes it is replaced by a brown 
translucent substance, which appears illuminated between crossed 
! The slices from which these drawings were made have been mislaid, and it is im- 
possible therefore in all cases to state the amount of magnification. 
