Febeuast 13, 1914] 



SCIENCE 



229 



during the past seven years by this depart- 

 hent in collaboration with a number of 

 contributing specialists, have been brought 

 together during the year in a volume now 

 in press under the title "The Salton Sea: 

 A Study of the Geography, the Geology, 

 the Ploristics and the Ecology of a Desert 

 Basin," as publication No. 193. A great 

 number of interesting questions in geog- 

 raphy, geology, botany, chemistry, micro- 

 biology, plant physiology, climatology, etc., 

 are discussed in this volume. Of these, an 

 instructive abstract is given by the director 

 in his current report. 



Among many researches carried on by 

 the director, mention may be made of his 

 cultivation of second and third generations 

 of mutants arising from ovarial treatments 

 of plants and resulting in further note- 

 worthy morphological and physiological 

 departures from the original parent stocks. 

 Of members of the departmental staff. Dr. 

 Cannon has extended his fruitful studies 

 of root systems of desert plants to include 

 the corresponding characteristics of trees 

 in the coastal climate of California and to 

 the problem of treelessness in prairie re- 

 gions. Dr. Forrest Shreve has given spe- 

 cial attention to the factors involved in the 

 transpiration of rain-forest plants and to 

 the effects of mountain slopes and climatic 

 conditions varying with altitudes and with 

 exposures. Dr. Spoehr has continued his 

 investigations of the action of light and 

 heat in producing chemical changes in 

 plant organisms, giving promise thus of 

 important advances in the newer field of 

 phytochemistry and photolysis 



Several collaborators have contributed 

 to the varied work of the department dur- 

 ing the year. Sections of the director's 



called Blake Sea, in honor of Professor Blake, who, 

 as geologist of the Williamson survey of 1853, first 

 accurately interpreted this remarkable depression 

 below sea-level. 



report are thus devoted to accounts of the 

 further experiments of Professor W. L. 

 Tower on the evolution of chrysomelid 

 beetles, for which facilities are provided 

 at the Desert Laboratory; to the physical 

 studies of Professor B. E. Livingston, 

 formerly a member of the departmental 

 staff, on the water relations of plants; to 

 the determinations of autonomic move- 

 ments in opuntias by Mrs. Shreve, whose 

 volume on "The Daily March of Trans- 

 piration in a Desert Perennial" is in press 

 as publication No. 194 ; to the investigation 

 of Professor H. M. Richards on the acidity, 

 the gaseous interchange and the respira- 

 tion of cacti; to the surprising properties 

 of the opuntias in fruit development, 

 brought to light by Professor D. S. John- 

 son ; and to the favorably progressing enter- 

 prise undertaken by the department, in 

 collaboration with Dr. N. L. Britton and 

 Dr. J. N. Rose, for a systematic determina- 

 tion of the distribution and relationships 

 of the cactus family of plants. 



DEPARTMENT OF EXPERIMENTAL EVOLUTION 



The work of the year in this department 

 records, among many other advances, addi- 

 tional contributions to the laws of human 

 inheritance; the results of further and 

 more conclusive studies of the transmission 

 of traits in plants of the genera Bursa and 

 Oenothera; and some preliminary indica- 

 tions of specially instructive investigations 

 in the field of biochemistry. The director 

 has divided his time between researches 

 based on breeding experiments carried on 

 at his station and studies of data bearing 

 on human heredity collected under the 

 auspices of the Eugenics Record Office, of 

 which he is also the directing head. In 

 addition to the researches carried on by 

 Doctors Banta, Gortner, Harris and Shull 

 of the resident staff, Dr. A. P. Blakeslee, 

 Dr. G. C. Bassett and Professor John H. 



