December 15, 1916] 



SCIENCE 



869 



any convenient shape fitted with a two-holed 

 rubber stopper through which are inserted two 

 glass tubes of 5 mm. bore, one projecting 5 

 cm. and the other 2.5 cm. from the stopper. 



Fig. 1. 



The operation of the apparatus is as follows : 

 the flask is filled with the nutrient solution 

 which is used in the culture jar and inverted 

 above it (or the glass tubes can be bent so that 

 the flask is above and at one side of the jar, and 

 thus out of the way of the plants). The solu- 

 tion flows out of the longer tube, the shorter 

 tube allowing the ingress of air. This flow of 

 solution from the longer tube may be stopped 

 by lowering the flask until the end of the 

 shorter tube comes in contact with the solu- 

 tion in the culture jar, which seals the end of 

 this tube and prevents the entrance of air and 

 thus the exit of solution from the longer tube. 

 The flask is adjusted so that the lower end of 

 the shorter tube is at a level desired as the 

 constant one, and as soon as the solution sinks 



(about 1.5 mm.) below this level either from 

 evaporation or the taking up of the solution 

 by the plant the air enters through the lower 

 end of the shorter tube, allowing the exit of 

 solution through the longer tube until the level 

 of solution in the culture jar rises to the end 

 of the shorter tube, which is sealed until the 

 water level sinks again. In the case of culture 

 experiments where the mouth of the culture 

 jar is covered it is only necessary to bore two 

 holes to admit the two tubes projecting from 

 the reservoir. Orton L. Clark 



Massachusetts Agricultural Experiment 

 Station 



SOCIETIES AND ACADEMIES 

 THE BOTANICAL SOCIETY OF WASHINGTON 

 The 112th regular meeting of the Botanical So- 

 ciety of Washington was held in the Assembly Hall 

 of the Cosmos Club, Tuesday, April 4, 1916. Fifty- 

 two members and five guests were present. Harry 



E. Fulton, George L. Keenan, Lester A. Bound, J. 



F. Clevenger, C. E. Temple, A. E. Aldous, Victor 

 Birekner and Forrest S. Holmes were elected to 

 membership. The following papers were pre- 



Botanical Explorations in South America: Dr. J. 



N. Eose. 

 Plants Domesticated in Peru: Mr. O. F. Cook. 



Mr. Cook gave a brief account of the agriculture 

 of the Incas with their wonderful terraces and 

 system of irrigation. Among the plants domesti- 

 cated by them were maize, beans, lima beans, pea- 

 nuts, quinoa (Clienopodium quinoa), red peppers 

 (Capsicum), mandioca, tomatoes, passion fruits, 

 sweet potatoes, tuberous Tropceolum and Oxalis, 

 arracacha (a celery-like plant), squashes and 

 pumpkins, gourds; and among the fruits, chiri- 

 moyas, lucumas and pepinos. The narcotic coca, 

 from which cocaine is now prepared, was also 

 grown. Mr. Cook's paper will be embodied in a 

 forthcoming article in the National Geographic 

 Magazine for May, 1916. 



The 113th regular meeting of the Society was 

 held in the Assembly Hall of the Cosmos Club, 

 Tuesday, May 2, 1916. Mr. Frank N. Meyer, geo- 

 graphical explorer of the U. S. Department of 

 Agriculture, was elected to membership. The pro- 

 gram consisted of the following papers: 

 Dr. Edward L. Greene, an Appreciation: H. H. 



Bartlett. 



As it was impossible for Mr. Bartlett to be pres- 



