90 



SCIENCE 



[N. S. Vol. L. No. 1282 



men. A binocular microscope or a 40-mm. 

 lens on a compound instrument should be 

 used. Tbe worms are usually to be found in 

 tbe bottom of almost any body of water where 

 there is mud mixed with decayed vegetation. 

 They can be kept indefinitely in aquaria 

 having a layer of mud on the bottom. 



F. H. Krecker 

 Ohio State University 



the cumberland falls meteorite 

 The stone described by Professor A. M. 

 Miller in Science for June 6 of the present 

 year, and of which the National Museum has 

 secured the major portion, proves of excep- 

 tional interest. In fact, it is scarcely too 

 much to say that it is one of the most re- 

 markable falls yet reported on the American 

 continent. The stone is a coarse enstatite 

 breccia, closely compacted, showing evidences 

 of compression while under a considerable 

 load and other indications of its having 

 formed a portion of a body of considerable 

 size, even of planetary dimensions. The most 

 striking macroscopical features aside from its 

 breceiated structure are the occasional en- 

 closures sometimes 4 or 5 cm. in diameter, of 

 a dark, near],y black, chondritie stone. I do 

 not recall another instance of so plain an ad- 

 mixture of stones of quite different type. 

 Such a stone finds no exact iwsition in the 

 classification of Brezina. Following out the 

 general plan, however, I have made a place 

 for it among the achondrites and designated 

 it a Whitleyite — a magnesia-rich stone brec- 

 eiated in structure, consisting essentially of 

 enstatite, poor in iron and carrying enclosures 

 of a black chondrite. The results of further 

 studies will be published elsewhere. 



Geo. p. Merrill 

 TT. S. National Museum, 

 Washington, D. C, 

 June 20, 1919 



THE THIRD EDITION OF THE BIOGRAPHICAL 



DIRECTORY OF THE AMERICAN MEN 



OF SCIENCE 



The compilation and publication of the 

 third edition of the Biographical Directory of 

 American Men of Science, postponed on ac- 

 count of war conditions, will now be completed 



as rapidly as possible. The work is intended 

 to be a contribution to the organization of sci- 

 ence in America, and the editor will greatly 

 appreciate the assistance of scientific men in 

 making its contents accurate and complete. 

 Those whose biographies appear in the second 

 edition are requested to forward such altera- 

 tions and additions as may be necessary or de- 

 sirable, and to obtain biographical sketches 

 from those who should be included or send 

 their names and addresses. All those engaged 

 in scientific work whose biographies are not in- 

 cluded in the second edition are requested to 

 send the information needed. For this purpose 

 the blank that is given on an advertising page 

 (ii) of the current issue of Science may be 

 used. 



It is intended that each entry shall contain 

 information as follows: 



1. The fuU name with title and mail address, the 

 part of the name ordinarily omitted in eorrespond- 

 enee being in parentheses. 



2. The department of investigation given in 

 italics. 



3. The place and date of birth, including month 

 and day. 



4. Education and degrees, including honorary 

 degrees. 



5. Positions with dates, the present position 

 being given in italics. 



6. Temporary and minor positions; scientific 

 awards and honors. 



7. Membership in scientific societies with offices 

 held. 



8. Chief subjects in which research has been 

 published or is now in progress. 



All those in North America should be in- 

 cluded in the book who have made contribu- 

 tions to the natural and exact sciences. The 

 standards are expected to be about the same 

 as those of fellowship in the American As- 

 sociation for the Advancement of Science or 

 membership in the national scientific societies 

 which require research work as a qualification. 



The compilation of the new edition will of 

 necessity involve much labor, but this will be 

 materially lightened if men of science will 

 reply promptly to this request. 



J. McKeen Cattell 



Gaeeison-on-Hudson, N. y. 



