1891.] MlCROSCOriOAL JOUHNAL. 185 



Thus Mr. II. II. Doubleduy, trom a book-case jjiled with works on 

 patent hiw, took a tin-and-glass device for showing the circulation in 

 a gold-fish's tail. It is an improvement on Kent's fish-trough, and 

 consists of a tank soldered to the top of the trough, large enough to 

 hold water to last the fish an hour or so. The fish is held in place by 

 a perforated tin cover weighted down by a bottle of shot. He also has 

 a Qiicen's revolving table fitted up with electric lights. Away out on 

 Florida avenue we found Dr. AUeger, with a good microscope, shav- 

 ing sections of brain and medulla. Woe be to the cats and rabbits in 

 that quarter. 



Then there is Mr. J. M. Yznaga, who rests from his law books by 

 peering down the tube, and takes an active interest in our Society. J. 

 M. Stedman can tell you about the fresh-water sponges. Dr. C. H. 

 Stowell is well known as the author of Histology of the teeth. Dr. 

 J. F. Scott studies pathology. Drs. Radclifie, Robbins, Richardson, 

 and Gibbs all had specimens on exhibition at our last soiree. Also 

 Mr. A. N. Skinner, of the Astronomical Observatory. Mr. Lewis 

 Mooers works in urinalysis and bacteriology. Dr. Collins Marshall 

 studies the diatoms, and Mr. John Grinstead the protozoa. 



Prof. Richard Foster, of Howard University, has biology for his 

 province. Dr. H. A. Dobson studies pond life. Dr. Cooper Curtice 

 is an expert on the subject of animal parasites. 



Dr. C. T. Caldwell is another of those wh6 still keep up an interest 

 in microscopy, though cumbered with a busy practice. He was one 

 of the charter members of the Society, and for several years Lecturer on 

 Histology and Urinalysis at the National University. 



But we pause, not for lack of material, but for lack of time to pursue 

 our investigations further. We wish simply to show that the Capital 

 is alive on the subject of microscopy, and we guarantee that the mem- 

 bers of the National Association will meet a warm welcome here. 



BACTERIOLOGY. 



The Microbe of Malaria. — Dr. F. Plehn, in the Zeitschrift fur 

 JJygiene, gives an account of some researches of his in this subject, and 

 a history of the opinions entertained by others during the last twelve 

 vears. In 1S79 Klebs and Tommasi-Crudeli described a bacillus found 

 by them in the water and soil of the Roman campagna, which they 

 were led by certain experiments to look on as the microbe concerned in 

 the causation of malarial fevers. In 1S80 Laveran found in the blood 

 of a subject of malaria in Algiers an organism not present in that of 

 healthy persons, which he caWed Plasmodium^ and maintained to be the 

 essential agent of the disease, in opposition to Klebs and Tommasi- 

 Crudeli. Zeihls in 1882, and von Schlens in 1884, discovered bacilli 

 and cocci in the blood of malarial persons in Italy, but made no exper- 

 iments. Previously to 1880 Koch's method of pure culture was un- 

 known, and though Klebs and Tommasi-Crudeli had never found the 

 bacilli in the blood of patients, the transfusions of Dochmann, Gerhardt, 

 Cuboni Golgi, and Marchiafava were considered to be conclusive. But 

 the Nestor of bacteriologists, Fred. Cohn, has since deprived the bacil- 



