900 The American Naturalist. [October, 
Borneo. Actinolite, smaragdite, and glaucophane schists are the most 
interesting foliated rocks studied. They contain, in addition to their 
characteristic components: epidote, garnet and orthoclase, most of 
which show the effects of torsion and pressure. A quartzite is remark- 
able in that it contains andalusite, sillimanite, rutile, zircon and tour- 
maline. The eruptives mentioned by the author as existing in this 
portion of the island are porphyrites, diorite, gabbro, peridotite, ser- 
pentine and a pyroxenite (augite-fels). 
Analysis of cretaceous lithographic limestones from various locali- 
ties in America and Germany give such discordant results that Vol- 
ney’ thinks it impossible to judge from analyses alone as to the com- 
mercial and technical value of such rocks. The organie matter in the 
stones contains nitrogen and traces of iodine. It is believed to be the 
residue of cretaceous fossils, and to be the cause of the peculiarly fine 
precipitation of the calcareous substance of good stones. 
The term *poikilite" has already been referred to in this note as 
descriptive of a rock-structure produced by the inclusion of many 
differently orientated particles of some mineral irregularly distributed 
within large plates of another mineral. This structure has been 
described by so many petrographers as occurring in so many different 
rocks that Williams" suggests its general use and proposes “ micropoi- 
celitie" as the term descriptive of the structure when observed micro- 
scopically. 
Some excellent examples of cone-in-cone structure in a concretion 
from the coal measures of Wolverhampton, England, are noted by 
Cole" as exhibiting clearly the crystalline structure of these bodies and 
their identity in mode of origin with spherulitic growths. 
e rocks occurring at Cingolina in the Euganean Hills, described 
by Tchichatcheff” a few years ago, have been reinvestigated by Graeff 
and Brauns,” who find augite-syenite and olivine-diabase cut by dykes 
of hornblende and augite andesites. The plagioclase of the latter rock 
includes a large mass of the rock’s groundmass which has crystallized 
largely as plagioclase with the same orientation as a thin zone of the 
same substance surrounding the corroded host. 
New Minerals—Sundtite—In some specimens of a silver ore 
from a mine at Oururo in Bolivia, Brégger finds masses and crystals 
-*Journ. Amer. Chem. Soc. 
? Jour. of Geol., Vol. 1, p. 17: 
23. 
^ Zeits. F. Kryst, XXI, p. 193. 
