X LIST OF ILLUSTRATIONS. 



TEXT FIGURES. 



Nereis (Ceratonereis) Alaskanensis, a New Polychaetous Annelid from 



Alaska. 



By A. L. Treadwell. 



1-4. Nereis {ceratonereis) alaskensis, new species. 1, 11th parapodium, X18; Page. 

 2, middle parapodium, X18; 3, ventral seta, X250; 4, dorsal seta, X250. 2 



Mineralogy of Some Black Sands from Idaho, with a Description of the 



Methods Used for Their Study. 



By Earl V. Shannon. 



1-9. Crystals of zircon 11 



10-14. Crystals of monazite 16 



15. Crystal of samarskite (?) from Idaho City 19 



16-19. Columbite from Idaho City 20 



20-21. Quartz and augite from Snake River 20 



22. Crystal of polycrase (?) from Idaho City 22 



23. Rutile crystal from Centerville 25 



24-28. Olivine, titanite, ilmenite, and allanite 26 



North American Ichneumon-flies of the Genera Clistopyga and Schizopyga. 



By R. A. Cushman. 



1. Apices of ovipositors: a, Clypta simplidpes; b, Lampronota americana Cres- 



son; c, Arenetra nigrita Walsh; d, Meniscus scutellaris Cresson; e, Cyllo- 

 ceria lugubris Cresson;/, Lampronota frigida Cresson; g, Lissonota ver- 

 berans Gravenhorst; h, Amersibia prionoxysti Rohwer 1 



2. Apices of ovipositors: a, Toxophoroides albomarginata (Creaaon) ; b, Phyto- 



dietus burgessi Cresson. Hind tarsal claw: c, Phytodietus burgessi Cres- 

 son 2 



3. Hind tarsal claws: a, Itoplectis conquisitor (Say); b, Ichneumon irritator 



Fabricius 2 



4. Apex of female abdomen of Toxophoroides albomarginata (Cresson) (A=hypo- 



pygidium) ' 



5. Apices of o\ipositors: a, Polysphincta texana Cresson; b, Hymenoepimecis 



wiltii (Cresson); Mandible: c, Hymenoepimecis wiltii (Cresson) 2 



6. Apex of ovipositor of Theronia fiilvescens Cresson 3 



7. Apices of ovipositors: a, Itoplectis conquisitor (Say); b, Apechthis picticomis 



(Cresson) 3 



8. Apex of abdomen of female of Coleocentrus occidentalis Cresson 3 



9. Aerolet of Labena grallator (Say) 4 



10. Areolets: a, Tromatobia rufovariata {Cresaon) ; b , Itoplectis conquisitor (Say) ; 



c, EpiuriLS alboricta (Cresson) 4 



11. Sessile first tergite of Perithous pleuralis Cresson 4 



12. Petiolate first tergite of Xorides yuhonensis (Rohwer) 4 



13. Mandible of Poem^nia americana (Cresson) 4 



14. Head of Schizopyga frigida Cresson, rear and front view: a, Gular submental- 



mental region; b, cardo and stipes of maxilla; c, labium; d, labial palpus; 



e, mandible; /, lobe or mala of maxilla; g, maxillary palpus 6 



