120 THE Microscope. 
EXCHANGES. 
(Hxchanges are inserted without charge. Subscribers having microscope apparatus for sale or 
exchange can announce the same without charge.) 
For EXCHANGE.—Fiddian Microscopic Illuminator, brass injecting syringe, Dr. Seilers sec- 
tion knife, warm stage with thermometer and gas chamber, ‘* Archiv fiir Microscopische Ana- 
tomie,’’ bonnd ; in exchange for first class Polariscope, collection of thin, mounted rock sections 
or collection of minerals—would also exchange for books, geological reports, or books on 
Mineralogy, Lithology and Geology. HENRY FROEHLING, 17 South 12th Street, Richmond, Va. 
FoR EXCHANGE.—Living specimens of Volvox Globator by mail for other ‘‘raw material” or 
mounted slides. Also one of Queen's dollar sets of untreated diatoms. Polycystines especially 
esired. ROBT. W. WOOD, JR., Revere St., Jamaica Plain, Mass. 
For EXCHANGE.—Mounted sections of ees lung of guinea pig. 
CHAS. BLASDALE, Decieho, Queens Co., N. Y. 
For EXCHANGE—Mound builders relics, pottery ge and Indian relics for medical books 
and surgical instruments. NRY W. COE, Mandan, Dakota. 
FoR EXCH ANGE—One Fiddian Microscopic Illuminator, one Brass injecting Syringe with four 
pipes and stop cock, one Microtome (Brass) Rivet, improved, with knife, one Dr. Seilers Section 
Knife and Carrier, one warm Stage with Thermometer and Gas C hamber in exchange for first 
class Polariscope with Sue is or collection of thin mounted Rock sections. 
NRY FROEHLING, 17 South 12th street, Richmond, Va. 
PRESH WATER ALGA, very numerous species, inclnding Volvox in abundance, Desmids of 
all kinds, Draparnaldia, Rivalaria, Anabaena Tetraspora &c., &¢ 
. M, ADAMS, Watertown, N. Y. 
GEEDS of Orthocarpus Purpurascens and slides of same in exchange for other objects mounted 
or unmounted. EDWARD GRAY, M. D., Benicia, California. 
WANTED—Well cleaned and selected Foramenifera for which cash will be paid or slides given. 
EDWARD G. DAY, Riverside, Conn. 
DIATOMACEOUS Earth from Denver, Colo., a ee for mounting material. 
. CHAMBERLIN, box 1597, Denver, Colo. 
ANTED.—Diatoms on Algze or in muds from all the tropical sea shores, especially from 
Puget Sound, Pensacola, Campeach Bay, Tampa Bay, and fossil earths from Petersburg, 
Popleine, Virg Rappahanock Cliff, Piscataway. New and old Nottingham, Maryland. Will give 
cash or beautiful diatom material from Europe in eat 
J.C. RINNBOCK, Wien, Simmering 14, Austria. 
i HAVE for exchange Stellate Hairs of Plants, Pollen, and Seeds; also various Diatoms, Polycis- 
tina, etc., anda variety of other good objects, all well mounted. W. FARNELL, Macon, Ga. 
FOR SALE.—A copy of Prof. Leidy’s great work on the Rhizopods has beons nae at this office for 
sale. Price, 87. 50. . STOWELL. 
I WILL exchange good histological for other first-class moun 
S. G. SHANKS, M.D., BT “Clinton Avenue, Albany, N.Y. 
AGABI INSECTS, pathological and other well mounted slides, in exchange for Pleurosigma, 
Trichina, Diatoms, Stained Bacteria, etc. J.O. STILLSON, Indianapolis, Indiana. 
Alretractive int A PELLUCIDA, or any other test diatom, mounted in ihe new medium, having 
refractive index of 2.4, can be procured from H. H. CHASE, M.D., Geneva, N.Y. 
—_— 
DIATOMACEOUS Clay from this place and slides of on and Diatoms to exchange for 
fine slides or material. E. H. RICHARDS, Woburn, Mass. 
ATHOLOGICAL, Histological and Miscellaneous Mounts. will be ee for mounted speci- 
mens or material. H. W, WESTOVER, M. D., St. Joseph, Mo. 
WANTED.—A copy of No. 1. Vol. IV., The Microscope ; will grtve slides in exchange, or cash. 
Very Truly, ENRY FROEHLING, Richmond, Va. 
ANTED.—Unmounted material, any kind; foram- 8 and diatoms preferred ; will give 
good exchange. . BOOTH, Longmeadow, Mass. 
ANTED. —Good 1-4; spy glass; will exchange good objectives, including new Gundlach 4-10 
of 80°. C. OUDERDONK, Rugby, Tenn. 
way ED. —Micrographic Die’y, 4thed. Will give Wales 1-10 immersion. 135°. 
u on a, e DR. ED. GRAY, Benecia, Cal, 
