480 



SCIENCE 



[N. S. Vol. XXXIV. No. 876 



botany, I am convinced that the great de- 

 velopment of plant ecology, of which we 

 have many indications, will not merely 

 lessen the momentum of the swinging 

 pendulum, but will draw the latter back 

 towards a renewed and critical study of 

 the British flora. That a revival of inter- 

 est in systematic botany will come through 

 the labors of those who are engaged in 

 survey work and other forms of ecological 

 study, is foreshadowed by the fact that Dr. 

 Moss has undertaken to edit a "New Brit- 

 ish Flora," which will, I believe, largely 

 fulfill the objects put forward by Professor 

 Trail in his presidential address. I trust, 

 however, that in addition to the eeologists, 

 those botanists who are interested in genet- 

 ics will contribute their share towards the 

 completion of our knowledge of critical 

 species, varieties and hybrids, all of which 

 offer such intricate problems alike to the 

 systematist and to the student of genetics. 



De Vries prefaced his lectures on 

 "Species and Varieties, their Origin by 

 Mutation," by the pregnant sentence: 

 "The origin of species is an object of ex- 

 perimental investigation," and this is 

 equally true of the study of the real and 

 presumptive hybrids of our British flora, 

 which may be investigated either synthet- 

 ically or, when fertile, also analytically, as 

 in some cases their offspring show striking 

 Mendelian segregation. Some good work 

 has already been accomplished in this di- 

 rection, but more remains to be done, and 

 we have here an important and useful 

 sphere of work for the energies of many 

 skilled plant-breeders. 



I would, therefore, like to plead for inti- 

 mate collaboration between all botanists, 

 hopeful that, as progress in the past has 

 come through the labors of men of wide 

 sympathies, so in the future, when studies 

 are bound to become more specialized, 

 there will be no narrowing of interests, 



but that the various problems which have 

 to be solved will be attacked from all 

 points of view, the morphological, the 

 physiological, the ecological and the system- 

 atic. Thus by united efforts and close 

 cooperation of botanists of all schools and 

 of all countries we shall gain the power to 

 surmount the difBculties with which our 

 science is still confronted. 



P. E. Weiss 



WOSK AT THE MARINE BIOLOGICAL STA- 

 TION OF SAN DIEGO DVBING THE 

 SUMMEB OF 1911 



Because a majority of the station's staff are 

 still holding college positions and hence can 

 be at La Jolla only during vacation time, the 

 summer months are the most active of the 

 year. This disadvantage must continue until 

 the income is sufficient to maintain opera- 

 tions at sea and a considerable part of the 

 work in the laboratory throughout the year. 



On the biological side the most important 

 event of the year is the final issuance of Mr. 

 E. L. Michael's " Classification and Vertical 

 Distribution of the Chsetognatha of the San 

 Diego Eegion " (Univ. Calif. Public. Zoology, 

 Vol. 8, No. 3, 165 pp.). In this the author 

 not only records all the species so far taken in 

 these waters and subjects the description and 

 taxonomy of the group to a critical examina- 

 tion, but deals quantitatively with the large 

 amount of data collected during the five years 

 from 1904 to 1909. 



The aim of the ecological aspect of the in- 

 vestigation was to ascertain the facts con- 

 cerning the distribution, seasonal and ver- 

 tical, of the organisms, and to see how far 

 these are correlatable with and hence de- 

 pendent upon the environmental factors of 

 light, and of temperature and density of the 

 water. Efforts were limited to these three 

 environmental factors simply because the 

 scope of the station's work up to this time has 

 not made it possible to extend the hydro- 

 graphic observations beyond these. 



While it is impossible to summarize here 



