Bricfer Articles. TH 
nial spring, and one egg failing to hatch, might have remained in 
the nest. I have seen such a locality where the still green and 
growing moss was slowly but surely becoming petrified (z. e., in- 
crusted by a mineral, deposited on its surface, by the water flow- 
ing over it), while other mosses had become wholly petrified. 
The vegetable substance in some specimens had decayed, while 
in others, only the fibres, incrusted by a calcareous substance, 
still remained. Specimens of petrified moss are not rare from 
the State of Michigan, but the locality I refer to was in the moun- 
tains of Lower California, and I am confident that the ‘‘water is 
dry’ a great portion of the year and would not interfere with nest 
building, shoulda bird select the site and begin operations before 
the rainy season. Ce Once: 
ALBINISM AMONG FLOwERS.—The editor has‘collected speci- 
mens of each of the following plants bearing only pure white flow- 
ers. Usually the whole plant was of a lighter green than that of 
the other plants which bore flowers of the normal hue. 
Delphinium decorum, F. &. M. Brodiza capitata, Bth. 
Linaria Canadensis, Dum. Sidalcea humilis, Gray. 
Mirabilis Californica, Gray. Gilia dianthoides, Endl. 
Orthocarpus purpurascens, Benth. Erythrzea venusta, Gray. 
A single plant of Mimulus cardinalis, Dougl., was once found 
in Lower California, with yellow flowers, which a well known 
botanist proposed to call a new species, but I advised him of its 
true character in season. 
The Erythrzea venusta, Gray, is often pure white and runs 
through the lighter shades of purple into its normal color. In 
the wet spring of 1884 I secured so many large and beautiful 
white-flowered specimens of this, as to lead Dr. Gray to inquire 
if it was not a valid species. The plant is very variable otherwise 
as to size and shape of foliage and flowers. C. R. Orcutt. 
EO eDINGS OF SCIENTIFIC SOCIETIES. 
SAN FRANCISCO MICROSCOPICAL SOCIETY,—June 12th, 1889. 
A. H. Beckenfeld, the Vice President, was present for the first 
time since recovering from his severe illness, and was cordially wel- 
comed. His contribution to the evening’s programme represented 
some fine specimens of Melacerta ringens, a tube-building rotifer, 
belonging to the family of wheel animalcules. This variety is 
considered the mcst beautiful of the species, and builds for its 
protection an ingenious tube, which it forms of round pellets that 
are elaborated in the interior of the animalcule, and securely 
gummed together with asecretion derived from the same source. 
This rotifer, when feeding, extends itself partly from its tube and 
by means of several rows of cilia produces a rapid rotary motion 
one set of cilia drawing a current of water containing food to its 
mouth, while another row ejects the debris by a current produced 
