68 Psyche [April 
ready to fly to the nearest growing elms. Scores of just such trunks 
us these may be seen on the streets and vacant lots of Cambridge and 
one can without difficulty strip off yards of the bark from them with 
the hands alone. If this bark is allowed to remain swarming with 
larvae it is an abiding and serious source of infestation and injury 
to growing trees. If property owners would acquaint themselves with 
this fact, and of the mischief thus caused both to their own trees and to 
those of the neighborhood, they would undoubtedly take immediate steps 
to have the bark removed. All dead trees and old trunks with loose 
bark should have it removed and burned by the first of May, 1910, at 
the very latest. This will prevent thousands of these beetles from flying 
to other healthy trees, and thus be the means of protecting them from the 
attacks of the beetle. 
Observations are to be continued throughout the spring and sum- 
mer, und a number of experiments will be conducted at the same 
time. These with further interesting data on the species will be re- 
served for a later paper. 
I wish to express my gratitude to Dr. W. M. Wheeler for the many 
helpful suggestions which he has given, and to Mr. C. T. Brues for 
his kind assistance in preparing the plates. 
EXPLANATION OF PLATES. 
Plate IV. 
Fig. 1. Pupa—S. multistriatus Marsh.— Ventral view. 
Fig. 2. Same — Dorsal view. 
Fig. 3. Same — Lateral view. 
Fig. 4. Larva — S. multistriatus.— Ventral view. 
Fig. 5. Same — Dorsal view. 
Fig. 6. Same — Lateral view. 
Fig. 7. 8S. multistriatus — Male. 
Fig. 8. S. multistriatus — Female. 
Fig. 9. Egg outline, S. multistriatus. 
Fig. 10. Mother and larval galleries of S. multistriatus. 
Fig. 11. Mother and larval galleries of Hylesinus opaculus Lec. 
Fig. 12. Hylesinus opaculus Lee. Dorsal view. 
Fig. 13. Same — Lateral view. 
Plate V. 
Fig. 1. Markings of S. multistriatus in bark of elm. 
Fig. 2. Showing “shot-holes” or exit holes of same. 
