OF WASHINGTON. 23 



pine and pinyon in the West, and bear some superficial resem- 

 blance to Phloeosinus. 



— Mr. Knab exhibited a box containing a remarkably fine 

 series of North American beetles of the genus Calligrapha, 

 among which were several new species described in a paper 

 in course of preparation. He called attention to the impor- 

 tance of knowing the plant on which insects were living as an 

 aid to the determination of the species. Mr. Schwarz, in com- 

 mending the work of Mr. Knab on this difficult genus, re- 

 marked on the great difficulty which has been experienced in 

 preparing a synoptic table of the various genera of American 

 Chrysomelini. The forms are numerous, and a table to be of 

 value must be accompanied by figures of the species. 



— Mr. Fiske presented the following paper : 



NOTES ON INSECT ENEMIES OF WOOD BORING 

 COLEOPTERA. 



By W. F. Fiske. 



During three seasons spent largely in the field upon forest 

 insect investigations, many notes have been collected upon the 

 natural enemies of the bark and wood-boring Coleoptera with 

 which these investigations have principally had to do. The 

 material thus collected, dealing, as it does, with many species 

 of widely different habits, is particularly of value, as it serves 

 to illustrate in a general way the existing relations between 

 this class of hosts and their insect enemies, at the same time 

 giving an idea of what developments may be expected along 

 this line. 



Early in the investigations it became apparent that there was 

 a remarkable difference between insect parasitism as it existed 

 in the wood-feeding Coleoptera, and in external-feeding in- 

 sects in general. This is most strikingly brought out in the 

 comparative importance of hyperparasitism. Dr. L. O. How- 

 ard, in a study of the parasites of Hcnierocampa (Orgyia) 

 leucostigma S. & A., estimated a total of 90 per cent of the 

 larvae and pupse infested by parasites, while at times as high 

 as 95 per cent of some parasites were destroyed by secondary 

 enemies. In a similar study of the parasites of the common 

 tent caterpillar {Malacosoma americana Fab.), made some 

 years ago in New Hampshire, it was found, when it became a 



