404 



SCIENCE. 



[N. S. Vol. II. No. 39. 



register a tenth of a gram. This amount 

 can be reduced to smaller quantities by sub- 

 dividing the curve recorded. 



6. Pressure, Normal Work, and Surj^his En- 

 ergy in Growing Plants, by Geokge M. Hol- 

 FEETY, Leipzig, Germany. This paper was 

 read by Professor Barnes in the absence of 

 the author. The general questions of press- 

 ure, interior and exterior; resistance, na- 

 tural and artificial ; work effects, normal 

 and extra, were discussed. Pfeffer's re- 

 sults showing the amount of pressure were 

 given, and the gypsum method and pressure 

 spring for root pressure were described. 



7. Notes on the Ninth Edition of the London 

 Catalogue of British Plants, by IST. L. Beitton, 

 Columbia College, New York City. The 

 author gave a comparison of the treatment 

 and nomenclature of genera in the cata- 

 logue common to Great Britain and north- 

 eastern North America. 



8. Oholaria virginica L., a Morphological 

 and Anatomical Study, by Theodoee Holm, 

 Washington, D. C. The systematic posi- 

 tion of Oholaria virginica L. was reviewed, 

 the statements being based iipon the 

 morphological characteristics and the anato- 

 my of the various organs of the plant. 



9. Botany of Yakutat Bay, Alaska, by Fred- 

 erick V. CoviLLE, Washington, D. C. This 

 paper was a review of a report upon a col- 

 lection of plants made at Yakutat Baj^, 

 Alaska, by Mr. Frederick Funston in 1892. 

 Attention was called to the more important 

 plants collected and a general account was 

 given of the relation of the plant life of the 

 region to , environmental conditions aud 

 native industries. 



The foregoing papers coOipleted the pro- 

 gram for Friday. Saturday being devoted 

 to general excursions no regular meetings 

 were held. On Monday Section F (Zoology) 

 and Section G (Botany) met in joint session 

 with the following program: 



10. Fungous Gardens in the Nest of an Ant 

 (Atta tardigrada Biickl.) near Washington, D. 



C, by W. T. Swingle, Washington, D. C. 

 The author first briefly reviewed the pub- 

 lished statements by Belt made in 1874, 

 that the Central American leaf-cutting ants 

 use the cut-up leaves for carrying into their 

 nests as a medium upon which to grow 

 fungi which serve as food for the ants. 

 The important work of Moller on the fun- 

 gous gardens of ants in south Brazil, pub- 

 lished in 1893, was then reviewed. Moller 

 showed that the ants not only cultivate a 

 fungus on chewed-up fragments of leaves, 

 but that thejr also make pure cultures of a 

 single species, and furthermore, that they 

 prevent the fungus from producing conidia 

 or other reproductive bodies. The fungus 

 under the action of the ants gives rise to 

 globular inflated hj^pha ends, which are in- 

 capable of germinating and which Moller 

 designated as kohlrabis. In July of tliis 

 year the author examined some colonies of 

 Atta tardigrada in the vicinity of Washing- 

 ton, and found within the nests a fungus 

 closely resembling that described by Moller. 

 Kohlrabis even larger and more perfect 

 than those described by Moller were found, 

 and from this and other evidence the au- 

 thor thinks that it is by no means improb- 

 able that the species will prove to be the 

 same as that described by Moller. 



11. Distinction between Animals and Plants, 

 by J. C. Arthur, La Fayette, Ind. The 

 author called attention to the present and 

 former use of physiological characters to 

 distinguish plants and animals, and to the 

 insufficiency of such characters to explain 

 the differences under consideration. The 

 following was suggested as expressing the 

 difference between animals and plants : 

 " Plants are oi-ganisms possessing in their 

 vegetative state a cellulose investment ; 

 animals are organisms possessing in their 

 vegetative state a proteid investment, actual 

 or potential.'' 



12. Variation after Birth, by L. H. 

 Bailey, Ithaca, New York. The author 



