104 REGINALD A. DALY 
may succeed in explaining post-Cambrian eruptive bodies and 
sequences. 
Azof region, Russia.—Guinsberg believes that the limestone- 
syntectic hypothesis is valid for the nephelitic and other alkaline 
rocks studied by him in the Azof (Mariupol) region, even though 
they do not make visible contact with limestones at all. He 
explains the origin of the nephelite-syenite by the mixture of a basalt-magma 
with limestone followed by a differentiation in alkali rocks and pyroxenite. 
Although the limestones were not discovered in this district, the presence of 
sedimentary rocks such as quartzite was established. In the neighboring 
district of Berdjansk, which forms the continuation of the same crystalline 
area, Morozewicz found among the crystalline schists together with quartzites 
also limestone and graphitic gneiss.? 
Reinhardswald, Germany.—Apel’s recent work on the Rein- 
hardswald district of Northern Germany gives the petrography. 
of a large number of volcanic necks.* The eruptives include: 
common basalt, dolerite, enstatite dolerite, trachydolerite, nephelite 
basalt, melilite-bearing nephelite basalt, leucite basalt, leucite 
basanite, limburgite, and nosean-bearing limburgite. Other types 
represent the transition between nephelite basalt and leucite basalt. 
This assemblage claims notice as another example of the close 
connection between alkaline varieties and feldspar basalt. Lepsius’ 
geological map of Germany seems to show that the alkaline-lava 
vents are here largely or wholly confined to areas underlain by the 
Muschelkalk at the time when the volcanoes were active, numerous 
vents filled with feldspar basalt and dolerite appearing specially 
in Bunter Sandstein areas. The writer has not been able to check 
this generalization by reference to a large-scale geological map of 
the region, but has thought the question involved might well be 
put on record. In any case the possible chemical influence of the 
Muschelkalk on the magmas which fluxed, stoped, or exploded 
their way to the earth’s surface needs investigation. The problem 
is complicated on account of the partial removal of the limestone 
by erosion since the volcanic epoch. 
A. Guinsberg, “Pierre le Grand 4 Pétrograde,”’ Amnnales de l’Inst. Polytech., 
XXV (1916), 435. 
2K. Apel, New. Jahr. fiir Mineralogie, etc., B.B. XX XVIII (1914), 525. 
