148 Annals Entomological Society of America [Vol. X, 



In the following year, 1900, Mr. E. M. Ehrhorn (5) pub- 

 lished a short description of a third Xylococciis, which he 

 found on a species of live oak in Stevens Creek Canyon, Santa 

 Clara County, California, and named Xylococciis querctis. 



In 1902 Professor Cockerell (2) included a brief description 

 of the Genus in ''A Co?itrihution to the Classification of the 

 Coccidce.'' Reference was made to the work of Low and of 

 Hubbard and Pergande, and the three known species listed. 



In 1905, Mr. S. I. Kuwana (7) presented a description of a 

 fourth species, Xylococciis matsumurce. Three years later a 

 second Californian species was found on the Monterey Cypress 

 trees near Pacific Grove, Monterey County, by Mr. G. A. 

 Coleman (4). He made some short notes on the species, naming 

 it Xylococciis macrocarpce. In the following year, 1909, Professor 

 Cockerell (3) referred Xylococciis matsumiircE to a new Genus 

 Matsucocciis on the basis of the anal tube and the character of 

 the last joint of the antenna. 



Dr. Leonhard Lindinger (9) in his textbook on Scale Insects, 

 published in 1912, gives a brief description of Xylococcus 

 filiferus Low. This has been taken from the original paper. 



In 1914, Mr. S. I. Kuwana (8) described a scale insect from 

 oak trees {Quercus serata) at Nishigahara, Tokyo, and other 

 places in Japan. He named it Xylococcus napiformis n. sp., 

 acknowledging Professor Cockerell' s assistance in the determi- 

 nation of the species. 



Of the two Californian species, Xylococcus macrocarpce 

 Cole, and Xylococcus quercus Ehrh., each stage in the life 

 history of the female and five stages in that of the male are 

 described in detail in this paper. A new species from alder 

 trees is described and I have called it Xylococcus alni n. sp. 

 It was collected at Wenatchee, in the State of Washington, by 

 Mr. E. J. Newcomer, of the Bureau of Entomology, who sent 

 it to the Entomological Laboratory of Stanford University. 



The distribution of this small group of Coccids presents 

 some interesting features. They have been found on three 

 continents, Europe, America, and Asia, and up to the present 

 time each species has been recorded from one host plant only, 

 Xylococcus filiferus Low, infesting linden trees in Lower Austria, 

 Xylococcus betulce Perg., infesting birch trees on the shores of 

 Lake Superior, Xylococcus quercus Ehrh., and Xylococcus 

 napiformis Kuw., infesting different species of oak trees, the 



