TABLE OF CONTENTS. XVU 



PAGE 



FAMILY II. UROCERIDAE (Wood-wasps). 



1. Sireae juvencus (Steel-blue wood- wasp) . . . 355 



2. S. gigas (Yellow wood-wasp) . . . 357 



FAMILY III. CYNIPIDAE (Gall- wasps) ... ... 358 



(#.) Diptera. 

 FAMILY L CECIDOMYIIDAE (Gall-gnats). 



1. Cecidomyia saliclperda (Willow gall-gnat) 360 



(<7.) Hemiptera. 

 FAMILY I. APHIDIDAE (Plant-lice). 



1 . Cliernies abietis (Spruce-gall Aphis) 361 



2. C. coccineus 364 



3. C. stroVdoUus (Larch Aphis) . ~ .364 



4. C. sibiricus 365 



FAMILY II. COCCIDAE (Scale-insects). 



1. Coccus fagi 366 



1. Lecanium hemlcryphum ......... 367 



Orthoptera. 

 FAMILY I. GRYLLIDAE (Crickets). 



1. Gryllotalpa vulgar is (Mole-cricket) . 368 



FAMILY II. ACRIDIIDAE (Locusts). 



1. Pachytylus migratorius (Migratory locust) 372 



List of Trees with the Insects which attack them . . 373 



PAET III. 

 PEOTECTION AGAINST PLANTS. 



CHAPTER I. 

 PROTECTION AGAINST FOREST WEEDS. 



SECTION I. GENERAL ACCOUNT. 



1. Definition ............ 386 



2. Classification 386 



3. Utility of certain weeds 390 



4. Damage done by forest weeds .... . 390 



5. Preventive measures .......... 395 



6. Remedial measures ......... 397 



F.P. /> 



