408 Scientific Intelligence. 



The group Tyroglyphidse is a most interesting and important 

 one, comprising, as it does, species which occur commonly upon 

 flour and meal, upon cheese, upon dried vegetables and drugs, 

 and upon various plant growths, usually moribund but occasion- 

 ally probably healthy. Interesting errors have occurred in pre- 

 vious observations upon mites of this family, and especially the 

 striking blunder of Cross, who believed that he had created one 

 species in his galvanic batteries. Another error has been the 

 description of species brought up as living in the depths of the 

 sea, when, in reality, the dredge had picked them off the surface 

 of the water on which they were floating. Systematists in other 

 groups in zoology will be interested to note that Mr. Michael 

 seems^ not disposed to agree to the opinion of the committee of 

 the International Zoological Congress, that the rule abolishing 

 names founded upon larval forms should hold with the Acarina. 

 Economic entomologists will be especially interested in Mr. 

 Michael's conclusion that Tyroglyphus phylloxera! Riley, a species 

 which was supposed to feed on the grape vine phylloxera and 

 which was imported from the United States into France to destroy 

 this great pest, is a synonym of T. mycophagns Megnin, does not 

 feed on living insects, and already existed in France. The plates 

 are very carefully done and are very beautiful. To the reader 

 not previously informed concerning the anatomy of the species of 

 Glycyphagus, for example, the representation of several species 

 of this genus may be a revelation. l. o. howaed. 



III.* Miscellaneous Scientific Intelligence. 



1. National Academy of Sciences. — The spring meeting of the 

 National Academy was held at Washington, April 19 to 22. 



Four new members were elected at this meeting : William 

 Morris Davis, Harvard University ; William Fogg Osgood, 

 Harvard University; William T. Councilman, Harvard Medical 

 School ; John U. N"ef , Professor of Chemistry, Chicago Uni- 

 versity. 



The following foreign associates were also elected : Prof. Dr. 

 Paul Ehrlich, Frankfurt ; Prof. Dr. H. Rosenbusch, Heidelberg ; 

 Prof. Emil Fischer, Berlin ; Sir William Ramsay, London : Sir 

 William Huggins, London ; Prof. Geo. H. Darwin, Cambridge; 

 Prof. Hugo de Vries, Amsterdam ; Prof. Ludwig Boltzmann, 

 Vienna. The Draper gold medal was presented to Prof. George 

 E. Hale of the Yerkes Observatory, for his researches in astro- 

 physics. 



The following is the list of papers presented : 



E. L. Nichols and Ernest Merritt : On fluorescence spectra. 



John Trowbridge : Spectra of gas at high temperatures. 



Theodore Lyman : Short wave-lengths of light. 



H. W. Morse : Spectra produced by the Wehnelt interrupter. 



George F. Barker : Note on radio-activity and autoluminescence. 



R. S. Woodward : A double suspension apparatus for determining the 

 acceleration of gravity. The compressibility of the earth's mass required by 

 the Laplacian law of density distribution. 



