848 



SCIENCE. 



[N. S. Vol. IX. No. 233. 



was noted. The descriptive methods applicable 

 to larger organisms here fail almost completely, 

 necessitating thatdiagnoses depend upon physio- 

 logical facts which receive little attention in the 

 descriptions of species belonging to groups of 

 greater structural complexity. 



At the 307th meeting, April 22d, Dr. S. D. 

 Judd gave an account of a recent observation 

 on chimney-swifts. A large flock was seen fly- 

 ing in a circle at great height and then gradu- 

 ally descending over a chimney of Georgetown 

 College, which they finally entered. Discus- 

 sion followed by Dr. L. O. Howard and Pro- 

 fessor E. L. Morris. The latter had noticed 

 that individual swifts leave the flock in small 

 parties of equal size until near the end of the 

 flight, when the remaining birds hurry into the 

 chimney without anj' regularity of proce- 

 dure. 



Professor T. D. A. Cockerell then opened the 

 regular program with a paper on the ' Faunse 

 and Faunulse of New Mexico,' in which he de- 

 scribed the various life-zones of New Mexico, 

 beginning with summits of the mountains. 

 The different belts are usually well marked 

 and are best designated by the names of abun- 

 dant and characteristic plants, such as the 

 spruce, piiion, scrub-oak, Dasylirion, Yucca, 

 Larrea and Atriplex canescens. One of the most 

 notable peculiarities of New Mexican condi- 

 tions is that the Larrea belt, supposed to repre- 

 sent the Lower Sonoran zone, occurs on the 

 bases of the mountains above Atriplex canescens, 

 which is considered a more northern type. 

 This apparent anomaly is explained by the fact 

 that the bottoms of the valleys are visited 

 by currents of cold air which render the 

 changes of temperature more rigorous than at 

 somewhat greater elevations. In all groups the 

 species of the New Mexican region are largel5'' 

 peculiar, doubtless to a considerable extent the 

 result of the fact that the naturalization of in- 

 troduced species is rendered extremely difficult 

 by the severe late frosts which native forms 

 avoid by remaining dormant through the gen- 

 erally very warm weather of early spring. 



In the course of the ensuing discussion Dr. 

 Merriam explained that the conditions de- 

 scribed by Professor Cockerell were consider- 

 ably different from those studied by himself in 



Arizona, while Mr. Osgood noticed a close 

 parallel in some of the valleys of California. 

 Mr. Coville suggested that Professor Cockerell' s 

 Atriplex might prove to be A. tetraptera, A, 

 canescens being a plant of more northern dis- 

 tribution. Dr. Loew related experience gained 

 while a member of the Wheeler Expedition 

 (1872-1875), which led him to the view that the 

 cold air which collects in the bottoms of valleys 

 sinks on account of its greater weight, causing 

 the warm air to rise along the slopes of the 

 mountains, which are thus maintained at a 

 higher temperature. Dr. Merriam resumed the 

 discussion and explained how in a similar way 

 upward currents of warm air are formed in val- 

 leys of more heated southwestern slopes of 

 mountains, frequently permitting the extension 

 of the flora and fauna of the valley to an alti- 

 tude sometimes 2,000 or 3,000 feet above the 

 normal. 



The next paper, ' Some Microchemical Re- 

 actions resembling Fungi,' by Dr. A. F. Woods, 

 explained that living protoplasm of plant cells, 

 when treated with certain reagents in common 

 use in histological investigations, will form pre- 

 cipitates which closely resemble and have been 

 mistaken for fungi supposed to be living as 

 parasites inside the cell. Dr. Woods had been 

 able, by adding very gradually such a reagent 

 (eau de Javelle), to observe the progress, in living 

 cells of the Bermuda lily, of a reaction closely 

 similar to the appearances which have been 

 described by Viala and others as a species of 

 Plasmodiopliora and which they believed to be 

 the cause of a disease of the grape. The pa- 

 per was illustrated by specimens and photo- 

 graphs. 



The program was concluded by Dr. Oscar 

 Loew with a paper on ' The Fermentation of 

 Tobacco. ' The processes of tobacco curing and 

 fermentation were described. The rise in tem- 

 perature and improvement in flavor during the 

 latter process have been in recent years uni- 

 formly ascribed to the presence of bacteria, and 

 many attempts to isolate the specific germ have 

 been made, several of which have been reported 

 as successful. Dr. Loew finds, however, that 

 bacteria have no part in these changes, that the 

 conditions are unfavorable for the growth of 

 bacteria, there being too little moisture, and 



