THE MICROSCOPE. Ale 
Pane eC Ee Pee Ono OC PETES: 
THE SAN FRANCISCO MICROSCOPICAL SOCIETY. 
HE semi-annual meeting of the Society was held at its rooms, 
120 Sutter street, June 12, 1889, Pres. Payzant occupying the 
chair. Mr. A. H. Breckenfeld contributed to the evening’s programme 
some fine specimens of Melacerta ringens, a tube-building rotifer, 
belonging to the family of wheel animalcules. This variety is con- 
sidered the most beautiful of the species, and builds for its protec- 
tion an ingenious tube, which it forms of round pellets that are 
elaborated in the interior of the animalcule, and securely gummed . 
together with a secretion 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 in an 
opposite direction. The tube and occupant are highly transparent 
and viewed by dark ground illumination never fails to excite 
astonishment and wonder at the sagacity displayed by nature in 
protecting these minute organisms from their enemies and furnish- 
ing them with such elaborate means for obtaining their subsistence. 
Mr. Breckenfeld also exhibited a slide of 4’cidiwm or “ cluster-cup 
fungus,” found infesting the scanty vegetation on Signal Peak, 
Yosemite Valley, some seven thousand feet above sea level. 
Dr. E. G. Clark exhibited some interesting slides of Cinnabar 
ore in Chalcedony, showing free mercury, a rare thing in the natural 
state. The gentleman also showed a beautiful mounting of crys- 
talized gold, displaying the peculiar fern-leafed disposition of the 
crystals produced by the galvanic current. 
The most notable feature of the evening was the exhibition by 
Charles C. Reidy of his collection of old and rare works of the early 
writers on microscopy. To the student and all interested in micro- 
graphical literature this was an opportunity rarely offered to exam- 
ine many volumes published by the pioneers in this branch of 
science, that are now very scarce. Mr. Reidy is devoted to the 
study of the Infusoria, and to facilitate his inquiries in that direc- 
tion the present collection has been slowly accumulated, though not 
without great difficulty and perseverance, many of his orders for 
special works having been several years in the hands of European 
book dealers before they were obtained, The different volumes 
cover the entire field of microscopical research from its very begin- 
ning, and contain a complete résumé of the evolution of optical 
