372 CARNEGIE INSTITUTION OF WASHINGTON. 



Mann, Albert, Washington, District of Columbia. Continuation of investi- 

 gations and preparations for publication of results of work on Diatomacece. 

 (For previous reports see Year Book Nos. 18-19.) 



The work of diatom investigation during the past year has been to a 

 great extent a continuation of several lines of research mentioned in 

 my former report. The study of the marine diatoms of the Philippine 

 Islands has been finished, so far as such unlimited fields of study can 

 be said to be finished, and the manuscript lacks only the retouching of 

 35 more microphotographs of new species in order to be ready for 

 publication. 



The study of the diatom flora of Woods Hole, Massachusetts, and 

 vicinity, has been carried forward. About a month was spent there 

 last summer and collections were made at the same localities and at 

 about the same period of the year as in preceding years. The ample 

 facilities (boats, laboratory apparatus, and helpers) supplied for this 

 purpose by the Bureau of Fisheries were made use of. Regular col- 

 lections have also been made each week throughout the year, both 

 dredgings and plankton hauls. It was also arranged to have adequate 

 collecting done at this place during the summer. These investigations 

 are now in their sixth year, and are nearing the time when deductions 

 as to seasonal variation, etc., may be drawn with some safety. Un- 

 doubtedly the work should be continued; a period of ten consecutive 

 years is probably the minimum time needed for supplying material 

 on which to base trustworthy estimates of the normal diatom flora 

 of this locality, or, indeed, of any other division of marine biology. 

 The laboratory work of cleaning and making microscopic preparations 

 of so large a number of samples is difficult; but so far all the material 

 secured has been prepared for study. 



The very important work of collecting plankton life along the 

 Atlantic Coast, chiefly in the Gulf of Maine, is being carried forward 

 under the direction of Dr. Henry Bigelow, of Harvard University, in 

 collaboration with the Bureau of Fisheries. The material collected 

 is largely diatoms and is being studied at this office. The reports 

 consist of an enumeration of all the species represented and their 

 relative abundance. New species, of which several have already been 

 found, will be adequately illustrated and described. This project has 

 an intimate bearing on the food-supply of our marine fishes and has 

 therefore a large economic as well as a purely scientific value. Studies 

 of this nature have been for a number of years in a far more advanced 

 state in Europe than here, especially along the coasts of France, 

 England, Belgium, Norway, and Sweden ; so that this work, now carried 

 on with scientific thoroughness on our side of the Atlantic is a cause for 

 particular gratification. Arrangements are made for continuing this 

 work during the coming year. 



Work additional to that reported last year on the fossil diatoms of 

 the Lompoc (California) bed has been done and will appear as a 



