IV THE SCX)LYTID BEETLES. 



The Genus Dendroctonus — Continued. Page. 



Specific distinctions 66 



Range or limits of specific variation 66 



Progressive modifications 67 



Distinction of major and minor di^dsions of the genus 68 



Plan of synoptic treatment 69 



S>aiopses of morphological and physiological characters 69 



Sj-nopsis of adult characters 69 



Synopsis of secondary sexual characters 73 



Synopsis of pupal characters 73 



Synopsis of larval characters 75 



Synopsis of gallery characters 76 



Table of distribution 77 



Table showing relation of species to host trees 78 



Table of host trees 79 



ReAision and systematic notes, with descriptions of new species. 79 



Distinctive generic characters 79 



Bibliography and synonymy of genus 80 



Division 1 81 



Subdivision A 81 



1. Dendroctonus brevicomis Le (^onte 81 



2. Dendroctonus barberi n . sp 85 



3. Dendroctonus convexifrons n . sp 87 



4. Dendroctonus frontalis Zimmermann 90 



5. Dendroctonus arizonicus n. S2> 95 



6. Dendroctonus mexicanus Hopkins 97 



7. Dendroctonus ■parallelocollis Chapuis 99 



8. Dendroctonus approximatus Dietz 101 



Subdivision B 105 



9. Dendroctonus monticolse Hopkins 105 



10. Dendroctonus ponderosx Hopkins 109 



11. Dendroctonus jeffreyi n. sp 114 



Division II 116 



Subdivision C 117 



12. Dendroctonus simplex Le Conte 117 



13. Dendroctonus pseudotsugse Hopkins 121 



14. Dendroctonus piceaperda Hopkins 126 



15. Dendroctonus engelmanni n . sp 130 



16. Dendroctonus borealis n. sp 133 



17. Dendroctonus obesus (Mannerheim) 135 



18. Dendroctonus rufipennis (Kirby) 138 



19. Dendroctonus murrayanse n . sp 140 



20. Dendroctonus punctatus Le Conte 142 



21. Dendroctonus micans (Kugelann) 143 



Subdivision D 146 



22. Dendroctonus terebrans (OliA'ier) 147 



23. Dendroctonus valens Le Conte 151 



24. Dendroctonus adjunctus Blandford 157 



Bibliography 159 



Preliminary Classification of the Superfamily Scolytoidea. 



A. D . HopTcins . . 165 



Introduction 165 



Position of the Scolytoidea 167 



General anatomy 168 



