64 CALIFORNIA ACADEMY OF SCIENCES. 



CONTRIBUTIONS TO THE LARVAL HISTORY OF PACIFIC COAST 

 COLEOPTERA. 



By J. J. EiVERS, University of California. 



The study of systematic entomology affords the student 

 but a dim idea of what insects are noxious and what are in- 

 noxious. The distinctive characters upon which the sys- 

 tematic entomologist builds classification need not be and 

 generally are not the characters of prime importance to the 

 economic entomologist. The names of many of the groups 

 of Coleoptera afford a slight generalized description which 

 is often misleading. In the present state of entomologic 

 science, where systematic is given precedence over biology, 

 it is dangerous to attempt to make a general statement of 

 the habits of a single genus and impossible to generalize 

 the habits of a group or family. 



The most valuable contribution to the life history of 

 American insects which is generally accessible is Dr. Pack- 

 ard's " Insects Injurious to Forest and Shade Trees."* In 

 his introduction the author states that this work is purely 

 tentative and designed to elicit the results of the observa- 

 tions of students of economic entomology. It is 'on that ac- 

 count that I feel at liberty to comment upon or question 

 certain of Dr. Packard's statements. 



On page 118, op. cit: Prionus laticollis, Drury, is noted 

 as injurious to the poplar. If Prionus destroys living trees 

 in other parts of America it has no such destructive habit 

 in California; in fact the charge against borers that they 

 destroy trees is a very old one, but by no means substanti- 

 ated by my own observations. P. Californicus goes through 

 its transformations in the roots of oaks, but these roots were 

 dead in every case observed by me and usually belonged to 



*U. S. Entomological Commission, Bulletin 7, Washington, 1881. 



6— Bull. Cal. Acad. Sci. II. 5. Issued April 23, 1886. 



