140 



THE AMERICAN MONTHLY 



[July, 1880. 



the center. He then showed glandular 

 epithelial cells from the scrapings of the 

 liver of an ox, much smaller, but similar 

 in some respects to those previously 

 shown. The third demonstration was of 

 cells from the mucous membrane of the 

 roof of a frog's mouth, which exhibited 

 the extraordinary action of the cilia. 

 These cells were fringed with hair-like 

 protuberances, known as cilia, that moved 

 with great activity and regularity, and 

 seemed endowed with independent life. 



The professor asserted that these cells 

 were very common in the human body, 

 noticeably in the bronchial tubes, where 

 the cilia, moving always in one direction, 

 were active in throwing off foreign sub- 

 stances injurious to health. The circula- 

 tion of blood in the feet of several frogs 

 rendered insensible by an injection of 

 woorara, was then shown. 



One of the most noticeable features of 

 the evening was the exhibition and use of 

 twenty Ann Arbor frogs, which the pro- 

 fessor brought with him as scientific cu- 

 riosities, stating that they were a distinct 

 variety peculiar to Ann Arbor, and of 

 great rarity, possessing a most curious 

 and interesting resemblance to the human 

 body in one or two respects. Apologizing 

 to the ladies present for so doing, the 

 professor gathered the thirty gentlemen 

 present at one side of the room and ex- 

 hibited the distinguishing characteristics 

 to them. 



Exchanges. 



An exceedingly interesting demonstra- 

 tion on the subject of crystalization was 

 given on the evening of June 2d before 

 the Griffith Club of Microscopy, by its 

 President, Prof. E. W. Wetmore, who il- 

 lustrated the subject by allowing various 

 solutions to crystalize under the micros- 

 cope. Prof. Wetmore, Fred. H. Seymour 

 and Prof. Charles H. Stowell were ap- 

 pointed a committee to arrange for a 

 public entertainment, at which, by the 

 use of a stereopticon with a microscope 

 attachment, a great variety of microscop- 

 ical objects will be enlarged and thrown 

 upon a screen, so as to be seen by a large 

 audience. They propose in this way to 

 show chrystals forming, polariscope ob- 

 jects, circulation of the blood, the pulsa- 

 tions of a frog's heart, and many forms of 

 living animalcules. 



We are pleased to observe the activity 

 shown by the members of ttj^ Griffith 

 Club, and although we cannot always 

 pubHsh the records of the meetings, which 

 we receive regularly, we will do so as fre- 

 quently as circumstances will permit. 



[Exchanges are inserted in this column without 

 charge. They will be strictly.Iimited to mounted 

 objects, and material for mounting.] 

 Polyzoa, Palates of Molliisca, Foraminifera, Sponge 

 and Holdthurian-Spicules, Synapta-Anchors, Chirod- 

 ota-Wheels, Echinus-Spines, Minute Sea Shells, in ex- 

 change for Polyzoa, Foraminifera, Histological and 

 Pathological preparations, etc. Also, a quantity of 

 Sea Shells in exchange for Land and Fresh-Water 

 Shells. 



F. M. HAMLIN, M. D., Auburn, N. Y. 



J. J. B. Hatfield, Arsenal Avenue, Indianapolis, 

 Indiana, will exchange Bleached Plant-Sections for 

 good Diatomaceous material. List furnished on ap- 

 plication. 



Pleurosigmas and other unmounted Diatoms, both 

 Fresh Water and Marine ; also Marine Algae, Ferns, 

 and a large quantity of miscellaneous microscopical 

 material in exchange for good mounted objects. 



M. A. BOOTH, Longmeadow, Mass. 



To exchange, well-mounted Slides of Hair for 

 mounted or unmounted specimens of hair from the 

 rarer animals ; lists exchanged. WM. HOSKINS, 



208 S. Halsted street, Chicago, 111. 



Nicely mounted Slides (opaque) of the Coal-tar 

 Derivatives, chemically prepared, crystalline in form, 

 showing their beautiful colors, in exchange for other 

 well-mounted material. Chemical name and formula 

 attached to each Slide. About a dozen varieties on 

 hand. F. L. BARDEEN, M.D., 



3054 Meigs street, Rochester, N.Y. 



Vanadate of Ammonia, (N H ) V O , Slides for 

 the Polariscope in exchange for other Slides. 



H. POOLE, Practical School, Buffalo, N. Y. 



Slides mounted from injected Frog's Gall-bladder, 

 Liver, Kidney, Stomach, Intestine and other parts, 

 exchanged for other good and interesting prepa- 

 rations. "C. BLASDALE, M. D., 



Jericho, Queens Co., N. Y. 



Well-mounted, selected and arranged Diatoms, for 

 good histological, pathological or anatomical prepara- 

 tion. State what you have, and terms of exchange. 

 W. W. RINER, Greene, Iowa. 



Foraminifera from Sponge-sand, Marl-sand, and 

 Chalk ; Transparent Prisms of Carbonate of Lime 

 from fossil Shells ; Fresh and Salt Water Diatoma- 

 ceous material ; Carapaces of Rhizopods ; polished 

 sections of Fossiliferous Limestones, Corals, etc., to 

 exchange for any microscopical material. 



K. M. CUNNINGHAM, 

 Box 874, Mobile, Ala. 



The American Monthly Micro- 

 scopical Journal. 



Issued on or before the fifteenth 

 day of each month. 



Correspondence should be ad- 

 dressed to the Editor, Romyn Hitch- 

 cock, 53 Maiden Lane, New York. 



Terms : $1.00 per year ; single 

 numbers, 15c. To foreign subscrib- 

 ers, 6^ francs, or 5 shillings sterling. 



