208 



SCIENCE 



[N. S. Vol. XLIII. No. 1102 



The committee of tKe board of trustees of 

 Cornell University on faculty participation in 

 tmiversity government has recommended that 

 three representatives of the faculty selected 

 by ballot shall sit at meetings of the board 

 with full powers except that of voting, and 

 that each faculty shall select committees to 

 meet with the general administrative com- 

 mittee of trustees. The board has approved in 

 principle the second recommendation and has 

 referred the whole question back to the com- 

 mittee for further conference with the faculty 

 committee. 



Dr. Willaed C. Fisher, whose enforced 

 resignation from Wesleyan University will be 

 remembered, has been appointed acting pro- 

 fessor of economics at New York University. 



At Princeton University, E. Newton Harvey, 

 Ph.D., has been promoted to an assistant pro- 

 fessorship of physiology. 



Professor William Stern, of Breslau, has 

 received a call from Hamburg to fill the chair 

 of philosophy and psychology vacant by the 

 death of Professor Ernst Meumann. 



DISCUSSION AND CORRESPONDENCE 



PARASITES OF THE MUSKRAT 



In the Journal of Parasitology^ Vol. 2, Wo. 

 1, p. 46, Linton describes cestode cysts fotmd 

 in the liver and omentum of a muskrat found 

 near Washington, Pa., in 1884. On the basis 

 of the size and shape of the hooks and the ap- 

 pearance of the bladderworm Linton con- 

 siders these to be Cysticercus fasciolaris, the 

 larval stage of Taenia crassicollis, a tapeworm 

 which is frequently found in the intestine of 

 the cat. 



The finding of Cysticercus fasciolaris in the 

 muskrat has been previously reported by Stiles 

 & Hassall, 1894, in " A Preliminary Catalogue 

 of the Parasites Contained in the Collections 

 of the United States Bureau of Animal In- 

 dustry, United States Army Medical Museum, 

 Biological Department of the University of 

 Pennsylvania (Coll. Leidy) and in CoU. Stiles 

 and Coll. Hassall." 



Dr. Allen J. Smith, of the University of 

 Pennsylvania, has written me that he has in 



his possession " a specimen of liver of the 

 muskrat which is tremendously enlarged and 

 riddled with Cysticercus fasciolaris." This 

 muskrat was trapped in the winter of 1904-05 

 near Philadelphia. 



Among fifty muskrats examined from Ne- 

 braska and Minnesota in no case have we 

 found the liver infected with any kind of 

 parasite. 



We have found in the intestine of one musk- 

 rat, shot at Lake Chisago, Minnesota, in Au- 

 gust, 1915, several hundred minute monostome 

 trematodes which represent a new species. 



These two parasites should be added to the 

 list given by us for the muskrat in Science, 

 N.S., Vol. 42, p. 570, and the Journal of Para- 

 sitology, 1915, Vol. 1, pp. 184r-197. 



Franklin D. Barkes 



The University of Nebraska 



THE USE OF THE INJECTION PROCESS IN 

 CLASS-WORK in ZOOLOGY 



It is often difficult or impossible in a labo- 

 ratory class in zoology to demonstrate path- 

 ways of fluids or food in certain animals, in 

 other than a purely structural way. Blood ves- 

 sels are injected and studied as so many 

 colored strings or tubes, and cavities and ducts 

 are explored with a probe, leaving much to the 

 imagination. During the summer course in 

 zoology at the University of Cincinnati, we 

 have made extensive use of the injection 

 method for studying the mechanics of these 

 structures, and their condition during opera- 

 tion. A glass tube is drawn out into a point 

 of any desired size, and attached to a rubber 

 hand bulb, either directly or by a rubber tube. 

 This apparatus, including a bunsen burner and 

 cutting file, is simple and cheap enough to be 

 included as a part of each student's equipment. 

 The injecting fluid used is usually India ink 

 or Prussian blue. The following example will 

 show how the method is used in studying the 

 circulation of a freshly killed crayfish. 



The animal is killed by chloroform or ether, 

 and the carapace dissected off. The student 

 then exposes the heart, being careful not to cut 

 any of the surrounding tissue. A fine-pointed 

 glass cannula is now inserted through a hole 

 made with the point of the glass injecting 



