February 20, 1920] 



SCIENCE 



187 



of eSort and of funds. The program of tlie 

 conference is in the hands of the Committee on 

 Pacific Exploration of the National Eesearch 

 CounciL 



The U. S. Bureau of Chemistry at Washing- 

 ton announces that the work on photosensitiz- 

 ing dyes b^un during the war for the Bureau 

 of Aircraft Production has met with such suc- 

 cess as to make possible the preparation in the 

 United States of dyes of all the recognized 

 types: pinaverdol (including Orthoohrome T), 

 cyanine, pinacyanol and dicyanine; and of a 

 new type useful for astrophotographic work. 

 The Color Laboratory of the bureau will place 

 its experience at the disposal of any manufac- 

 turer who wishes to prepare these important 

 photographic aids for the American market; 

 and pending their commercial availability is 

 prepared to supply them to users at a price 

 fixed by the secretary of agriculture. 



UNIVERSITY AND EDUCATIONAL 



NEWS 



Dr. Edgae F. Smith, provost of the Univer- 

 sity of Pennsylvania since 1911, tendered his 

 resignation to the board of trustees on Febru- 

 ary 9. Dr. Smith became professor of chem- 

 istry in the University of Pennsylvania in 

 1888. 



Dr. Jacob Gould Schurman has resigned 

 the presidency of Cornell University. Dr. 

 Schurman, previously professor of philosophy, 

 became president of Cornell University in 

 1892. 



Dr. Charles W. Dabney has resigned the 

 presidency of the University of Cincinnati, 

 which he has held since 1904. 



Dr. John M. T. Finney, Baltimore, has 

 declined the offer made him by Harvard Uni- 

 versity and will continue his connection with 

 the Johns Hopkins Hospital and Medical 

 School. 



Dr. H. H. Lane, who has since 1905 been 

 head of the department of zoology of the 

 University of Oklahoma, has accepted a posi- 

 tion for nffid; year as head of department of 

 zoology, of Phillips University, Enid, Okla- 

 homa. 



DISCUSSION AND CORRESPONDENCE 



BLOOD-INHABITING PROTOZOA FOR CLASS 



USE 



At the present time there are several large 

 and important groups of Protozoa that remain 

 unknown to students of biology chiefly be- 

 cause they are not easy to obtain when they 

 are needed. One of these groups that is of 

 added interest because of the economic im- 

 portance of some of its members contains the 

 hemoflagdlates, including the trypanosomes. 

 Trypanosomes are responsible for the hmnan 

 disease known as sleeping sickness, that is 

 prevalent in certain parts of Africa, and for 

 Chagas' disease in South America. They 

 also cause diseases in domestic animals such 

 as surra, nagana, murrina, mal de eaderas 

 and doiu-ine which result in great losses every 

 year. 



The first trypanosome described was foimd 

 in the frog in 1843 and was given the name 

 Trypanosoma rotatorium. Specimens belong- 

 ing to this species oeciu' in the frogs of this 

 country, particularly in the " water " frogs 

 such as the green frog, Rana clamitans, and 

 the bullfrog, Rana catesbiana, but they are 

 present usually in small numbers and not all 

 frogs are infected. If it is desired to obtain 

 for study this type 8i)ecies the centrifuge may 

 be used to concentrate the specimens. Blood 

 may be obtained from an etherized frog and 

 mixed to prevent clotting with a solution of 

 sodiimi citrate made up as follows: sodium 

 citrate, IJ grams; sodiiun chloride IJ grams; 

 water 250 c.c. After centrifuging for about 

 ten minutes the trypanosomes, if present, will 

 be found in a layer at the top of the mass 

 of red blood cells. 



A much more simple method of furnishing 

 trypanosomes to a large class of students is 

 to collect a few newts, Diemyctylus viridescens, 

 from the water. Tobey in 1906 first described 

 the species in these newts naming it Try- 

 panosoma diemyctyli. He foimd them pres- 

 ent in every specimen that he had pvirchased 

 in an animal store in Boston. The writer 

 has had a similar exi)erience with newts col- 

 lected for him in Pennsylvania. Seventy- 



