652 



SCIENCE. 



[N. S. Vol. IX. No. 227. 



' Occurrence of Paleotroohis in Volcanic Rocks in 

 Mexico,' by H. S. Williams. 



' Origin of Paleotroohis,' by J. S. Diller. 



' Association of Argillaceous Eocks with Quartz 

 Veins in the Region of Diamantina, Brazil, ' by O. A. 

 Derby. 



Goldschmidtite, a New Mineral,' by W. H. Hobbs ; 

 ' Hydromica from New Jersey, ' by F. W. Clarke and 

 N. H. Barton. 



'Powellite Crystals from Michigan,' by C. Palaobe. 



' Volatilization of the Iron Chlorides in Analysis, 

 and the Separation of the Oxides of Iron and Alu- 

 minum,' by F. A. Gooch and F. S. Havens. 



' Descriptions of imperfectly known and new Actini- 

 ans, with Critical Notes on other Species, V,' by A. 

 E. Verrill. 



' Preliminary Note as to the Cause of Root-Pres- 

 sure,' by R. G. Leavitt. 



' Study of some American Fossil Cycads, Part III.,' 

 by G. R. Wieland. 



Professor L. V. Pirsson, who holds the chair 

 of geology in the Shefiield Scientific School of 

 Yale University, has become an associate editor 

 of the Journal in the place of the late Professor 

 Marsh. 



After the close of the current volume, in 

 April, the Zoological Bulletin, edited by Profes- 

 sors Whitman and Wheeler, of the University 

 of Chicago and published by Messrs. Ginn & 

 Co., will be continued under the title the 

 Biological Bulletin and be published under the 

 auspices of the Marine Biological Laboratory. 

 The scope of the Bulletin will be enlarged so as 

 to include General Biology, Physiology and 

 Botany. It will further include occasional re- 

 views and reports of work and lectures at the 

 Laboratory. The Bulletin will be open, as 

 heretofore, to scientific contributions from any 

 source. 



SOCIETIES AND ACADEMIES. 

 THE PHILOSOPHICAL SOCIETY OF WASHINGTON. 



The 500th meeting of the Society was cele- 

 brated on April loth by a dinner at Rauscher's. 

 About fifty members were present. After 

 coffee had been served, the President, Mr. O. H. 

 Tittmann, in his usual felicitous manner, called 

 on the past Presidents of the Society who had 

 honored the banquet by their presence. Seven 

 were present, namely, Newcomb, Harkness, 

 Eastman, Dall, Clarke, Baker and Bigelow. 



Interesting remarks were made by each of these 

 gentlemen, on the past history of the Society, 

 its relation to present scientific progress, and its 

 future sphere of usefulness. Informal inter- 

 course was had for a short time after adjourn- 

 ment. 



E. D. Preston, 



Secretai'ij. 



entomological society op WASHINGTON, 

 APRIL 18, 1899. 



Under the head of Exhibition of Specimens 

 and Short Notes, Mr. Howard exhibited a vial 

 full of specimens of a species of a Peripatus just 

 received from some unknown correspondent in 

 Trinidad. 



Mr. Schwarz showed a specimen of Chrysina 

 erubescens Bates. The determination he said 

 was somewhat doubtful, but probably correct. 

 The species is a distinct Central American 

 form, but the specimens showed were found in 

 Madera Canyon, south Arizona. The insect is 

 probably a grape feeder. 



Dr. Dj'ar showed specimens of Megalopyge 

 krugii, Dew., collected by Mr. Busck in Porto 

 Rico. The larva was described by Dewitz in 

 his original communication, but so briefly that 

 additional points were mentioned. 



Mr. Howard asked whether Mr. Busck had 

 been stung by this larva, and Mr. Busck re- 

 plied that the first one which he found had 

 fallen on the back of his hand and produced 

 severe pain and inflammation which lasted for 

 three days. 



The first paper of the evening was read by 

 Mr. Schwarz and consisted of a continuation of 

 the Hubbard correspondence from the South- 

 west. The letter read at this meeting con- 

 tained a discussion of the insect fauna of Dasy- 

 lirion wheeleri. In discussion Mr. Pollard asked 

 whether the agave and other large plants of 

 that region have similar insect fauna. Mr. 

 Schwarz replied that the agave is the only 

 liliaceous plant of that region which has an in- 

 sect enemy which attacks it when healthy. 

 This is a lepidopterous larva of the genus 

 Megathymus. The communication was briefly 

 discussed by Messrs. Cockerell and Ashmead, 

 Mr. Cockerell stating that two Coccids had been 

 found upon the Dasylirion, but that both species 



