99 



SUMMARY. 



The results of this experiment show conclusively: 



That the Bordeaux mixture, properly applied to the plants during their period 

 of growth, does materially lessen the smut. 



That the ammoniacal copper carbonate was not as effective as the Bordeaux 

 in preventing the smut. 



That frecjuent applications of the fungicides are necessary during the growing 

 period of the plant in order to he effective. 



A Xew Station- for Pi.edporika Lamfornica Shaw. By Seaeraxce 

 Bfrrage. 



lUiring an investigation of the sanitary condition of the Wabash and Erie 

 (^'anal as it runs through Lafayette, made in the laboratories at Purdue in Sep- 

 tember of the present year, Pleodortna was found in considerable abundance in 

 the canal water. This comparatively new member of the Vohoj: family was first 

 described by Walter R. Shaw, of Leland Stanford University, who found the 

 plant in a ditch in Palo Alto in September, 1893 ( " Botanical Gazette," Vol. 1!), 

 p. 279 *. ."^ince then D. M. Mottier has reported it in Bloomington, Indiana, 

 in May. 1894, and Messrs. Clinton and Burrill in Havana, Illinois ('' Botanical 

 Gazette,'" Vol. 19, p. 383 ), in June of the same year. It is now possible to add 

 another station in Indiana, namely, Lafayette. 



The microscopical examinations were made according to the Sedgwick-Rafter 

 method, which has been used for several years by the Massachusetts State Board 

 of Health in the enumeration of microscopical organisms, exclusive of bacteria, 

 in water supplies. The average number of Pleodorina in one cubic centimeter of 

 the canal water was four. The census of other organisms found in the same sam- 

 ples included, on the vegetable side, Ilydrodiclion, Chara. and Splrogyra. too large 

 and abundant to enumerate; Diatoms, per cubic centimeter, eight; OscUlaria, 

 fifty-six: Aitubaena, three; Sceii'dei^miis, one; Protocoecui<, eight; Crenothrix, ten; 

 Pandorimi. one; viold hyphae, three; and. on the animal side, principally in/us- 

 oiia. as Peridiniiim, two hundred and ninety-six; j\lonas, four: Trachelamonas, 

 three; Dinobryon. three: and a few Pod/era and Acarina. The water was quite 

 turbid, and had the general appearance of dilute sewage, and in fact the water of 

 the canal wa^ evidently polluted. This shows the nature of the water in which 

 PleodoritHi seems to flourish in Lafayette, and also many of its companions. 



