95 



the loss to agricutlture from rusted grain, or to our forests from 

 rusted pine, nevertheless, under the microscope a rust-in\aded 

 plant cell shows us a very delicate interrelation between host 

 and parasite. I have even on occasion taken up literary cudgels 

 in defense of Jack-in-the-pulpit rust when it has been used as 

 an example of a toxic parasite. (22, 51) The development of 

 mutualism is an interesting matter. It is chief among those 

 other reasons because of which I welcome these twenty-six 

 rusts as members of the Norton plant community. 



Rtist 



1. Aecidium putictaliim Pers. 



2. Aecidium samhuci Schw. 



3. Caeoma nitens Burrill 



4. Chrysomyxa cassandrae Tranz. 



5. Chrysomyxa pyrolae Rostr. 



6. Cronartium ribicola F. de Waldh. 



7. Gymnosporangium clavariaeforme 



DC. 



8. Gymnosporangium juniperi-vir- 



gimanae Schw. 



9. Gymnosporangium nidus-avis 



Thaxter 



10. Kuehneola albida Magnus 



11. Melampsora Bigelowii Thiim. 



12. Peridermium acicolum Under w. & 



Earle 



13. Peridermium comptoniae Orton & 



Adams 



14. Phragmidium potentillae-canad- 



ensis Diet. 



15. Puccinia antirrhini Dietel & Hol- 



way 



16. Puccinia asparagi DC. 



17. Puccinia coronata Corda 



18. Puccinia graminis Pers. 



19. Puccinia malvacearum Mont. 



20. Puccinia sorghi Schw. 



21. Puccinia taraxaci Plowr. 



22. Puccinia violae DC. 



23. Uromyces caryophyllinus Wint. 



24. Uromyces caladii Farl. 



25. Uromyces houstoniatus J. Sheldon 



26. Uromyces trifolii Lev. 



Host 



Hepatica acutiloba DC. 



Samhucus canadensis L. 



Rubiis villosus Ait. 



Chamaedaphne calyculata (L.) Moench. 



Pyrola americana Sweet. 



Pinus Strobus L. 



Juniperus communis L. & Amelanchier 



oblongifolia (T. & C). Roem. 

 Juniperus virginiana L. & Malus sp. 



Juniperus virginiana L. & Amelan- 

 chier oblongifolia (T. & G.) Roem. 

 Riibiis sp. 

 Salix sp. 

 Pinus rigida Mill. & Solidago sp. 



Myrica asplenifolia L. 



Potentilla canadensis L. 



Antirrhinum sp. 



Asparagus officinalis L. 



Avena sp. 



Berberis canadensis Mill. 



Althaea rosea Cav. & Malva rotundi- 



folia L. 

 Zea Mays L. 



Taraxacum officinale Weber 

 Viola sp. 



Dianthus caryophyllus L. 

 Arisaema triphyllum (L.) Schott. 

 Houstonia caerulea L. 

 Trifolium sp. 



