THE MILLARDETIAN PERIOD 79 



6. Trade crops. 7. Vegetable and garden crops. 8. Tree 

 fruits. 9. Small fruits. 10. Grapes. These are again di- 

 vided into the individual crops composing each crop 

 group and under each plant, according to the parts 

 affected, as, for example, wheat: I. Diseases and pests 

 of the heads. II. Diseases and pests of the leaves and 

 haulms. III. Diseases and pests of the seedling. IV. 

 Diseases and pests of the roots. V. Diseases and pests 

 of the ripe seed. Finally, under each of these the diseases 

 are arranged according to the chief symptoms exhibited. 

 The atlas published in collaboration with H. Boltshauser 

 has appeared in several series beginning in 1896. 1 Each 

 colored plate, reproduced from large hand-painted charts, 

 many of which he showed me with much pride, is ac- 

 companied by a brief text of description or explanation. 



Germany produced during this period another patho- 

 genetist of marked ability and who fortunately is still 

 living and contributing to the etiologic phase of the 

 science. I refer to Heinrich Klebahn, botanist of the 

 Hamburg Botanical Institute. He is best known for 

 his contribution to our knowledge of the hetercecious 

 rusts. 2 His first paper, published in 1887, deals with a 

 rust fungus. Since 1892 3 he has published almost annu- 

 ally reports of his cross inoculation work with hetercecious 



1 For a list of these series see Lindau and Sydow, Thesaurus, 1 : 767. 

 They appeared under the general title of Atlas der Krankheiten und 

 Beschadigungen unserer landwirtschaftlichen Kulturpflanzen. Each 

 series deals with the diseases and pests of some crop group, as, for ex- 

 ample, "Krankheiten und Beschadigungen der Getreidearten." 



2 Klebahn, H. : Die wirtswechselnden Rostpilze. Versuch einer 

 Gesamtdarstellung ihrer biologischen Verhaltnisse, pp. I-XXXVII + 

 1-447, Berlin, 1904. 



3 Klebahn. H.: Kulturversuche mit heterocischen Uredineen, Zeitschr. 

 Pflanzenkr., 2 : 258-275, 332-343, 1892. 



