566 



SCIENCE. 



[N. S. Vol. XXI. No. 537. 



tion is the same, whether the bulb is placed 

 at 6 em. or 6 m. from the fog-ehamber. 

 But only in the former case {D = 6 cm.) 

 is the effect cumulative; only for very 

 short distances will persistent or large nu- 

 clei appear if the exposure is prolonged 

 several minutes. I have, therefore, sus- 

 pected that the radiation from the X-ray 

 bulb is twofold in character, that the in- 

 stantaneous effect (fleeting nuclei) is due 

 to a gamma-like ray quick-moving enough 

 to penetrate several millimeters of iron 

 plate appreciably even for D = 6 meters ; 

 furthermore, that the cumulative effect 

 (persistent nuclei) is due to X-light prop- 

 erly so called, which produces the usual 

 effects subject to the law of inverse squares. 



Carl Barus. 



Brown University, 

 Providence, U. S. A. 



THE BIOLOGICAL LABORATORY OF THE 

 BUREAU OF FISHERIES AT WOODS 

 HOLE, MASS. REPORT OF WORE 

 FOR THE SUMMER OF 1901* 



The laboratory was opened to investi- 

 gators on the fifteenth of June, and con- 

 tinued in operation until near the close of 

 September. During the whole or a part 

 of this period twenty-eight investigators 

 were engaged in work upon problems of 

 marine biology. A brief statement of the 

 special subjects of research will be given 

 below. 



T. EQUIPMENT, STAFF, ETC. 



The same portions of the station were 

 occupied as during the preceding season, 

 and need not again be detailed; the steam 

 vessels Fish Hawk, Phalarope and Bhie 

 Wing were in service during the whole or 

 a part of the season ; the zoological library 

 of Brown University was again generously 

 placed at the disposal of the laboratory. 

 Two fish pounds were set, one being placed, 

 as formerly, in Buzzards Bay, not far from 



* Keport to the Commissioner of Fisheries by 

 the director of the laboratory. 



the station, the other -being planted at No 

 Mans Land, a small island a few miles to 

 the south of Marthas Vineyard. Here a 

 camp was located, several assistants being 

 detailed to tend the trap for a period of 

 about seven weeks. 



The staff of the laboratory, for the past 

 season, consisted of a director and seven- 

 teen assistants, together with a matron, two 

 janitors and a chambermaid. To this list 

 should be added a clerk and a collector, 

 permanently attached to the station, and 

 the crews of the various vessels. Of the 

 assistants, three had immediate supervision 

 of certain branches of the survey work; 

 three others had charge respectively of the 

 library, the supply room and the fish traps ; 

 while the remaining eleven rendered vari- 

 ous services in the laboratory or in the 

 field. Mention should also be made here 

 of seven salaried investigators, employed 

 by the bureau to conduct independent re- 

 searches. 



The plan of having a 'seminar' or re- 

 search club, for the discussion of work in 

 progress at the laboratory, was successfully 

 continued, some of the meetings being 

 largely attended by outsiders, as well as by 

 investigators at the station. 



n. BIOLOGICAL SURVEY. 



The biological survey of the neighboring 

 waters, commenced during the preceding 

 season, was actively continued. The Fish 

 Haivk was at the disposal of the laboratory 

 for some five weeks, during which period 

 she was chiefly engaged in dredging work 

 in Buzzards Bay. In all 66 'stations' were 

 dredged by this vessel, these being located 

 at regular intervals over the bottom of the 

 entire bay. The supervision of this branch 

 of the work was intrusted to Mr. Leon J. 

 Cole. Dredging in Vineyard Sound was 

 likewise continued. A number of the sta- 

 tions (18) of the preceding year Avere again 

 located and dredged, but the principal work 



