1885.| Botany. 601 
a temperature of 264° C., it passed from the monoclinic to the 
triclinic modification, having a distinct system of twinning lamella 
and an inclined extinction of 2° against the cleavage lines on oP. 
The same feldspar was also found to undergo a like alteration 
when subjected to pressure, thus experimentally proving the sug- 
gestion of Van Werveke! that many plagioclase crystals owed 
their twinning striation to the pressure to which they had been sub- 
jected in rocks. 
HyYPERSTHENE-BASALT.—A correction should be made to the 
statement in the Petrographical Notes (NATuRALIST, April, 1885, p. 
395), that Mr. J. S. Diller was the discoverer of the new rock 
type hypersthene-basalt. This rock was described by Messrs. 
Hague and Iddings in 1883,? in their Note on volcanoes of 
Northern California, Oregon and Washington Territory, and 
again in 1884%, in their Notes on the volcanic rocks of the Great 
basin. It is, however, here spoken of as olivine-bearing hypers- 
thene andesite, or as hypersthene-bearing, basalt. These authors 
regard the hypersthene and olivine as playing complementary 
réles in the lavas, 7. e., one being a singulosilicate and the other the 
corresponding bisilicate ; in case a basalt grows slightly more acid 
the hypersthene replaces the olivine, which therefore diminishes 
in quantity as the other increases. In this way hypersthene- 
basalt may be regarded as a connecting link between basalt and 
hypersthene-andesite. 
BOTANY.‘ 
PaxviiaterOn OF THE WILD Onion (ALLIUM CERNUUM).—The 
wild onion grows in masses along the banks of shady streams in 
August. The flowers are arranged in dense umbels, which are 
nodding as their specific name implies. They are of a beautiful 
rose ae presenting an attractive appearance, when seen from a 
distanc here are six stamens, which arrive at maturity one 
after the other, the outer row developing first (Fig. 1). In this 
Fig. 1. Fig. 2 Fig. 3. Fig. 4. 
Fig. 1. Antheriferous Be: Fig. 2. bars state. Fig. 3. The three processes 
with nectaries (#) at their junction. Fig. 4. A stamen attached to an inner member 
of the perianth and enfolded by it. 
successive development they resemble the usual course in the an- 
r maa Jahrbuch für Min., etc., 1883, 11, p. 87. 
2 American Journal of Science, ' Sept., 1883, p. 233. 
ib, Tp, June, 1884, p, 457 and p. 
4 Edited by Professor CHARLES E. BESSEY, TIA Nebraska. 
