Dawson — Addendum to Paper on Eozoon, 131 
mineral first mentioned is compared by Hoffman to laliliinite, to wliicli 
jollyte is also related in physical characters as well as in com230sition. 
Under the names of fahlunite, gigantolite, pinite, &c., are included a 
great class of hydrous silicates which, from their imperfectly crystalline 
condition, have generally been regarded, like serpentine, as results of 
the alteration of other silicates. It is, however, difficult to admit 
that the silicate found in the condition described by Hoffman, and 
still more the present mineral, which injects the pores of palaeozoic 
Crinoids, can be any other than an original deposition, allied in the 
mode of its formation to the serpentine, pyroxene, and other minerals 
which have injected the Laurentian Eozoon, and the serpentine and 
glauconite, which in a similar manner fill tertiary and recent shells." 
The second point to which I would refer, is the alleged occurrence 
of the structures of Eozoon in connexion with crystals of spinel, 
from Amity, l^ew York. I have examined the specimens of this 
mineral and its matrix, within my reach, with the following results: — 
A specimen from that locality in the collection of M'Gill College, and 
another in that of Dr. Hunt from that vicinity, contain in spots, 
remains of casts of canals similar to those Eozoon Canadense apparently 
belonging to fragments of this fossil. Erom the general structure and 
aspect of these specimens, however, I infer that they are portions of a 
bedded rock and not a veinstone. In fact, they closely resemble 
specimens in the collection of the Geological Survey, from New- 
borough, Ont., which have been described by Dr. Hunt; in which 
large grains and imperfect crystals of chondrodite, sometimes one- 
fourth of an inch in diameter, '■ ' mark the planes of stratification in 
a bedded limestone." Both chondrodite and spinel are by him stated 
to occur in the bedded crystalline limestones of the Laurentian, as well 
as in the calcareous veinstones (Eeport Geol. Canada, 1866, pp. 206 
and 213). It is worthy of remark that there are numerous other 
specimens in the collection of Dr. Hunt from Amity and the adjacent 
region, which are clearly calcareous veinstones, often containing chon- 
drodite, spinel, pyroxene, &c., which exhibit no trace of Eozoon, 
Giimbel also, in his extensive examination of crystalline limestones in 
1865, could detect no Eozoon in the coarsely crystalline carbonate of 
lime with chondrodite, from Amity; and, I think, it will be found 
that carbonate of lime holding Eozoon, associated with chondrodite 
and spinel, either formed part of a bedded rock, or possibly, in some 
cases, may have been derived from a fragment of such rock enclosed in 
a veinstone. 
