NORTH AMERICAN APTERYGOGENEA. 



BY HARALD SCHOTT. 

 [With Plates xvi-xviii.] 



By the kindness of Dr. H. W. Harkness and through 

 the mediation of Dr. Gustav Eisen, I have received for 

 determination a collection of Apterygogenea, belonging 

 to the California Academy of Sciences, as well as a col- 

 lection belonging to Dr. Eisen personally. The exam- 

 inations have to me been very interesting as leading to 

 the discovering of several forms new to the science and 

 giving an opportunity to control and correct several details 

 concerning the Californian Collembola the descriptions of 

 which were published by me in the year 1891. The types 

 of both the above collections are now in the California 

 Academy of Sciences of San Francisco. 



The collection contains specimens found in upper and 

 Baja California, Arizona and the Pacific Coast of Mexico, 

 all having been collected by Dr. Eisen and Frank H. 

 Vaslit. In my examinations of the Thysanura, I have 

 consulted the following works: II Sistema dei Tisanuri, 

 by B. Grassi and G. Rovelli (Estratta dal Naturalista 

 Siciliano, An 1889-90), Monograph of the Collembola 

 and Thysanura, by Sir John Lubbock, London, 1873, 

 Synopsis of the Thysanura of Essex County, Mass., by 

 A. S. Packard, Jr. (in Fifth Annual Report of the 

 Trustees of the Peabody Academy of Science for the 

 year 1872), and Campodea? en Familie af Thysanurernes 

 orden ved Fr. Meinert (Naturhistorisk tidskrift, Kjo- 

 benhavn, 1865, p. 400). 



In the collection the following genera and species are 

 represented: 



Pkoc. Cal. Acad. Sci., 2d Ser., Vol. VI. March 20, 189G. 



