PETROLOGICAL ABSTRACTS AND REVIEWS 379 
rocks and volcanic sheets, and Quaternary moraines and alluvium. The 
most widely distributed rock in this region is a hornblende-bearing 
biotite-granite. The Devonian sheets are trachydolerites and alkali- 
trachyte. The later abyssal rocks are granites, syenites, nephelite- 
syenites, gabbros, and essexites, and of these all but the gabbros and 
essexites, which form small bosses, occur as batholiths. The nephelite- 
syenites are represented by lujavrites and other rare types, several of 
which have been given new names. 
Naujaite is a sodalite-syenite, but since the latter term was used 
for rocks of quite different characters by Steenstrup, Lindgren, and 
Hibsch, the new name is proposed for a nephelite-syenite rich in sodalite, 
and having a peculiar poikilitic texture. The mode, computed from the 
chemical analysis and compared with the thin section, gives for two 
different specimens: sodalite 31 (54), nephelite 18 (5), eudialyte 3 (2), 
microcline 20 (6), albite 10 (—), ainigmatite —(2), aegirite 10 (12), 
arfvedsonite 1 (5), analcite 7 (14). 
Sodalitite is almost exclusively made up of sodalite with very small 
amounts of aegirite, feldspar, and eudialyte. 
Kakortokite is a coarse grained, trachytoid (foyaitic) nephelite- 
syenite. It differs from ordinary foyaite in its high percentage of dark 
constituents. Three varieties are described: black, white, and red. 
The minerals are eudialyte, alkali-feldspar, nephelite, arfvedsonite, 
and aegirite. Sodalite, ainigmatite, biotite, rinkite, fluorite, and epis- 
tolite, as well as zeolites, may be present. The chief minerals in the 
black rock are aegirite and arfvedsonite. They are present in about 
equal amounts and, while very abundant in other cases, make up 65 
per cent of the black rock. The chief mineral of the white rock is 
microline-microperthite, the chief mineral of the red, eudialyte. 
Agpaite is a general name given to the rocks occurring at Ilimausak, 
and includes the sodalite-foyaite, naujaite, lujavrite, and kakortokite. 
VALETON, J. J. P. “Kristallform und Léslichkeit.” Ber. math- 
phys. Kl. kon. sdchs. Gesell. Wiss., Leipzig. LXVII (1915), 
INOW 7S PP) 5 OntISS Os, ple i. 
Determines that there is no difference in the solubility of alum in 
different directions. The laws of growth and solution must be explained 
on different grounds than solubility differences. 
