and Union of Supposed Distinct Species. 305 
Dr. Thomson, the only chemist who has analyzed Dysluite, 
reckons all the iron as peroxide, and as the principal basic 
constituent of the mineral, which, in his view, consists of the 
aluminates of iron, zinc and manganese. Rammelsberg, in 
stating the analysis, has given both oxides, and. the atoms of 
alurhina and peroxide of iron, as put down by him, are 22.80, 
and those of the isomorphous bases — protoxide of iron, pro- 
toxide of manganese and oxide of zinc— are 7.83 (7.891) ; 
thus giving the same ratio as that above stated. 
But other reasons may be urged why Dysluite should be 
regarded only as a variety of Automalite. 1 have seen speci- 
mens on which there were crystals well claiming the name of 
Dysluite, as well as others equally entitled to the name of 
Automalite; while there were yet others, evidently passing 
from one into the other, ——the bright and perfect crystals of 
Automalite gradually losing their lustre, becoming porous, - 
comparatively brittle and soft. I think if these circumstances 
had been attended to in the early history of the mineral, the 
name Dysluite would long since have departed from the cata- 
logue of mineral species. 
Polyadelphite. As Dana, in the new edition of his min- 
eralogy, has very properly included this mineral under the 
species garnet, I merely refer to it, to give further evidence of 
the correctness of his opinion from circumstances connected 
with its occurrence at the locality. It is evidently a granular, 
imperfectly crystallized yellow garnet, and the specimen which 
I received, ten years ago, from Prof. Nuttall, contains mechan- 
ical mixtures which it would be impossible to separate from it, 
*0 as to give us entire confidence in its analysis. To these, I 
eve, we may attribute its departure in composition from 
common brown or yellow garnet, though it does not differ 
much from the brown garnet of Franklin, analyzed both by 
r. Thomson and Mr. Seybert. : 
Beaumontite of Levy, and Lincolnite of Hitchcock. Ina 
Paper read before the Boston Society of Natural History, 
and since published in their Journal, and in the American 
