1890.] MICROSCOPICAL JOURNAL. 105 



MICROSCOPICAL SOCIETIES. 



Washington, D. C. — L. M. Mooers, Sec'y. 



io6th Meeting-^ May ij. — The Microscopic Life of the District (of 

 Columbia) was the subject of an interesting paper by Dr. W. H. Sea- 

 man. 



All living forms may he divided into plants and animals. In plants 

 the forms which especially require the microscope in their investiga- 

 tion, in descending the scale of complex structure, are, in order, the 

 ferns, mosses, lichens and algae, and fungi. 



The first three of these have been listed and publisiied in the Guide 

 to the Flora of the District, b}' L. F. Ward, as Bulletin No. 22 of the 

 National Museum. The ferns were treated by the botanists of the Poto- 

 mac vSide Club, who began the work on the District flora after Brere- 

 ton, and the mosses were done by Rudolph Oldberg, afterwards revised 

 by Rev. E. Lehnert, and with the lichens published in a supplement 

 to the flora. Good work has been done on the fresh-water algae by 

 Prof. E. S. Burgess, but no list has yet been published. The diatoms 

 and fungi yet remain to be studied. 



A complete series of animal life is not found in the District, because 

 many of the orders are found only in salt water. Many of the smaller 

 insects require the microscope for their identification and study, and 

 this part of microscopic zoology has for some time been diligently pros- 

 ecuted at the Department of Agriculture, by Prof. Riley and his as- 

 sistants. 



After pointing out the descending scale of animal life, and citing the 

 best authorities and text-books to be consulted in their study, the Doctor 

 hoped that some member or mevnbers of the Society would be found 

 with opportunity to carry on and complete the history of the life forms 

 of the District. 



Washington, D. C. — L. M. Mooers, Sec\y. 

 loyth Meeting, May 2y. — Prof. Richard Foster exhibited a new 

 class microscope made by Qiieen & Co., explaining its construction 

 and illustrating its advantages for class work. Its simplicity, ease of 

 manipulation, and the readiness with which it can be used by a large 

 class, make it a very desirable instrument for this line of work. A 

 number of ''homemade" accessories were shown by Mr. L. M. 

 Mooers, comprising a warm stage, bull's-eye lens mounting, eye shade, 

 slip for mounting opaque objects, etc. 



108th Meeti7ig\ June 10. — The microscope as an aid in the dete(ition 

 of arsenic, was the subject of a paper by Dr. E. A. Gibbs. The vari- 

 ous tests for determining the presence of arsenic were illustrated, and 

 slides exhibited showing the use of the microscope as a confirmatory 

 test. At the conclusion of the discussion brought out by the paper, Dr. 

 Stowell exliibited a number of rare and interesting objects, among them 

 a rib from a small skeleton covered with a hairy growth, the origin and 

 nature of which, thougli already the subject of considerable investiga- 

 tion and correspondence, seems to be yet undetermined. This closed 

 the meetings of the Society for the season, and adjournment was had 

 to tlie fouith Tuesday of vSeptember. 



