118 THE AMERICAN MONTHLY [J une, 
microscope, becomes comparatively easy, and valuable experiments of inoculation 
upon living animals, etc., are made possible. The immensely valuable results already 
obtained by Pasteur, Koch and many others, are a guarantee of what may be reason- 
ably hoped for in the near future by the study of a subject, the immense importance of 
which can hardly be over-estimated. 
A most cordial vote of thanks was unanimously tendered Dr. Mouser for his very 
interesting and instructive exhibition. A. H. BRECKENFELD, ec. Secr. 
O 
SAN FRANCISCO, CAL. 
A meeting of the San Francisco Microscopical Society was held on May 11th, Pres- 
ident Wickson occupying the chair. 
The Secretary announced the receipt, from Dr. Thomas Taylor, Microscopist of the 
Department of Agriculture, Washington, D. C., of the last annual report of that 
department, accompanied by a number of colored plates, photo-engravings and pho- 
tomicrographs, illustrating the crystallography of butter and of other animal fats. A 
great deal of work is now being done by Dr. Taylor, in regard to this important subject, 
and his investigations, thus far, show that the fats of different animals differ in their 
crystallization. For example, if small quantities of butter and of lard and of beef-fat be 
separately boiled and slowly cooled, for, say twenty-four hours, the resulting crystals — 
will show very marked differences under the microscope. The normal butter-crys- 
tal is large and globular, polarizes brilliantly and shows a well-marked St. Andrew’s 
cross. That of lard shows a stellar form, while that of beef-fat has a foliated appear- 
ance. In course of time, as the butter loses its freshness, the globular crystals degen- 
erate and gradually merge into peculiar rosette-like forms. These different stages 
of crystallization could be plainly seen in the photographs sent. Specimens of butter- 
crystals had been prepared by the Secretary and were shown as resplendent objects 
under polarized light. Favorable comments were made on the excellent work done 
by this branch of the Government, in breaking up the traffic in unwholesome and 
fraudulent ‘butter compounds. ’ 
Specimens of the interesting little alga Chlamydococcus pluvialis were sent in by 
Dr. H. W. Harkness. The bright-red globose cells bear a strong resemblance to 
those of C. zva/is—the microscopic plant producing the phenomenon known as ‘ red- 
snow.’ A slide of the latter, gathered in the Sierra Nevada Mountains, near Donner 
Lake, was also exhibited to show the close similarity between the two plants. In fact, 
the later authorities are inclined to regard them as not specifically distinct, but differing 
only in habitat. C. péevial’s being the plant as found in rain water, and C. zzvalis 
as found in snow. The cells possess the remarkable property of retaining vitality 
after being kept dry for years, for as soon as moisture is supplied, vegetation again 
commences. 
Communications were read, requesting exchanges of diatomacee, and of native 
gold crystals. 
A committee, consisting of Prof. Hanks, Mr. Hyde and Col. Kinne, was appointed 
for the purpose of compiling and perpetuating the early history of the society. 
Chas. C. Reidy exhibited a slide of Foraminifera under dark-field illumination, the 
latter being obtained in remarkable perfection by means of the Bausch and Lomb 
form of Abbe condenser. 
A committee was appointed for the purpose of arranging details for the annual re- 
ception, to be held on the 28th inst., and the society adjourned for two weeks. 
A, H. BRECKENFELD, ec. Secr. 
ee 
Essex County, N. J. 
The Essex Co. Microscopical Society met at the residence of Jay L. Smith, Thurs- 
day evening, May 5th, subject, microscopical technique. 
After the regular business was transacted, Mr. Smith gave a practical demonstration 
of his modification of Dr. Reeves’ method of cutting sections. The only part of the 
operation that was omitted was the clarification of the object in turpentine. As this 
takes some two or three hours, he placed the object in turpentine some hours before 
the meeting. An account of the method will be found in the February number of 
this Journad. 
Dr. Geo S. Allen showed some seventy slides illustrating the histology of a devel- 
oping pig’s tooth, each slide contained from ten to twenty sectionscut by the ribbon 
