1896.] Geology and Paleontology. 579 
essential points having already been discussed by Hobbs, Grimsley and 
others. 
Petrographical Notes.—The rocks of the Laurentian area to the 
north and west of St. ies eromë, Quebec; are briefly referred to by Adams’ 
as gneisses, tl , limestones, quartzites, ete. Some 
` of the gneisses are eruptive and others are probably sedimentary. 
Miller and Brock’ have found in Frontenac, Leeds and Lanark 
Counties, Ontario, granites, gabbros, scapolite and pyroxene rocks of 
Laurentian age cut by dykes of quartz gabbro containing re 
of pyroxene and plagioclase. 
Keyes? declares that the granites and porphyries occuring in the 
eastern portion of the Ozarks, in Missouri, “ are very closely related 
genetically, and are to be regarded as facies of the same magma,” the 
porphyry being the upper and surface facies of the granite. 
GEOLOGY AND PALEONTOLOGY. 
Canadian Paleontology.—In addition to the vertebrates (rep- 
tilia and batrachia) and land snails discovered by Sir Wm. Dawson in 
the interior of erect trees in the coal formations of Nova Scotia, and 
described by him in various scientific publications, fragments of arthro- 
pods have been found in the material collected. These were submitted 
for examination to Mr. Samuel Scudder who published a preliminary 
report in 1882, and now, after completing his study, gives these addi- 
tional facts. A few species of Myriapods show traces of the bases of 
spines; the ventral plates in Archiulus are very broad ; two new spe- 
cies of this genus are recognized ; two species of Mazonia are indicated, 
one of which (M. acadica) confirms the separation of this genus from 
Eoscorpius ; a facetted eye taken from a reptilian coprolite shows the 
presence of a true insect, probably a cockroach. 
A report upon the Cenozoic Hemiptera of British Columbia, by the 
same author, comprises descriptions of nineteen species. Mr. Scudder 
calls attention to the great variety among these insects. Among the 
Homoptera, every specimen must be referred to a distinct species, and 
6 Ann. Rep. Geol. Surv. of Can., Vol. VII, J., p. 93. 
7Can. Record of Science, Oct., 1895. 
ê Bull. Geol. Soc. Amer., Vol. 7, p. 363. 
