268 



SCIENCE 



[N. S. TOL. XXIX. No. 737 



of America) was held in the Eastern High School, 

 Baltimore, Maryland, December 28, 1908, to Jan- 

 uary 1, 1909, under the presidency of Professor 

 W. F. Ganong. Over sixty members were in at- 

 tendance at the meeting, which seemed generally 

 regarded as unusually successful. The arrange- 

 ments made by the local committee for the Amer- 

 ican Association concerning rooms, stereopticons, 

 etc., proved entirely adequate and satisfactory. 



The officers of the society for 1909 are: 



President — Professor Eoland Thaxter, Harvard 

 University. 



Vice-president — ^Mr. A. F. Woods, Bureau of 

 Plant Industry. 



Treasurer — Dr. Arthur Hollick, New York Bo- 

 tanical Garden. 



Secretary — Professor D. S. Johnson, Johns Hop- 

 kins University. 



Councilors — Professor J. M. Coulter, University 

 of Chicago; Professor Wm. Trelease, Missouri 

 Botanical Garden; Professor F. E. Clements, Uni- 

 versity of Minnesota. 



Five associate members were elected to full 

 membership, and eight botanists were elected to 

 associate membership. 



The next annual meeting of the society will be 

 held in conjunction with the American Associa- 

 tion for the Advancement of Science. 



Important features of the program were the 

 special addresses given on invitation of the council 

 by Professor Roland Baxter, of Harvard Uni- 

 versity, and Professor J. C. Bose, of Presidency 

 College, Calcutta ; the addresses on " Vascular 

 Anatomy," by J. M. Coulter and E. C. Jeffrey; 

 the symposium on " Present Problems in Ecology," 

 with papers by H. C. Cowles, B. E. Livingston, 

 C. H. Shaw, V. M. Spalding and E. N. Transeau; 

 and, finally, the estimates of Darwin's work in 

 botany, given at the Darwin Memorial Session of 

 the society by Wm. Trelease, H. M. Richards and 

 F. E. Clements. 



It is planned to publish in full in The American 

 Naturalist the addresses on " Vascular Anatomy," 

 on " Plant Ecology," and those given at the Dar- 

 win Memorial Session. Reprints of these papers 

 'f will then be distributed to members of the society. 



The scientific session of the society on Thursday 

 morning, December 31, was devoted to the reading 

 of papers which were organized into two programs 

 given simultaneously. Abstracts of these papers 

 follow: 



The Structure and Organization of Pediastrum: 

 Professor R. A. Haepeb, University of Wis- 

 consin. By title. 



Illustrations of Some of the Types of Coralline 

 Algce: Dr. M. A. Howe, New York Botanical 

 Garden. 



The speaker exhibited a series of lantern-pho- 

 tographs, illustrating the form, structure and 

 habits of growth of the dominant types among the 

 Corallinaceae. The specimens selected for photo- 

 graphing were collected chiefly on the shores of 

 Newfoundland, Maine, Florida, Bermuda, the 

 Bahamas, Jamaica and Porto Rico. Certain cal- 

 careous Chlorophycese, often confused with the 

 Corallinaceae by the earlier naturalists, were also 

 illustrated. The structure of several genera of 

 unsegmented corallines was exhibited by means of 

 photomicrographs. Of special biological interest 

 were photographs showing corallines growing at- 

 tached to living corals and indicating competitive 

 struggles for existence between calcareous plants 

 and calcareous animals. The speaker alluded to 

 the wide geographic range of the corallines and 

 to the discovery by the late Professor Kjellman 

 of extensive beds of Lithothamnion glaciate off the 

 coasts of Spitzbergen and Nova Zembla, more than 

 twelve degrees north of the Arctic circle. Men- 

 tion was made, also, of recent investigations tend- 

 ing to show that reef-building and land-formation 

 in certain regions have been due to the growth 

 of calcareous plants fully as much as to the 

 corals. 



The Male Gametophyte of Dioon edule: Professor 

 C. J. Chambebiain, University of Chicago. 



The staminate cones of Dioon edule shed their 

 pollen in September, the male gametophyte at this 

 time consisting of a prothallial cell, a generative 

 cell and a tube cell. The generative cell divides 

 in October, forming a stalk cell and a bedy cell, 

 and the latter divides in the following spring, 

 giving rise to two sperms. The sperms are formed 

 within two sperm mother cells and swim freely 

 within the mother cells before they escape into 

 the tube cell. 



The blepharoplasts are first distinguishable in 

 the body cell and are very probably of nuclear 

 origin. The radiations about the blepharoplasts 

 arise by a transformation of the cytoplasm, but 

 owe much of their subsequent growth to granules 

 of nuclear origin. During the transformation of 

 the blepharoplast into the spiral band, the band 

 is closely connected with the nucleus, both mor- 

 phologically and physiologically. 



The mature sperms not only swim actively by 

 means of cilia, but have an amceboid movement. 

 In escaping from the pollen tube, they may be 

 constricted to less than one fourth their normal 



