104 



dates back to Malpighi-^ who observed on grape leaves the 

 white* coat of hairs caused by mites, ^ This formation was 

 not investigated more closely until the end of the 18th 

 century,' Persoon (1798) considered the abnormal hairs to 

 be fungi, which he united into a new gernls "Erineum". Link 

 (111) and Fries* differentiated" several genera, according to the 

 Ifform of the hairs, Unger^ , corrected their error and 

 ascertained that the threads described by the authors named 

 were not fungi, but hypertrophied epidermal cells. The next 

 step forward was brought about by the knowledge that the 

 described hypertrophies were caused by mites. Fee was the 

 first to discover them among the Erineum hairs^, and to 

 recognize them correotly as the cause of mal- formation. The 

 development and life-history of the mites have been deter- 

 mined 0inoe then by the numerous investigations of. Siebold, 



1« Anatome Plantarum^ London, 1675-1679. 



2. 3?he " Brineum populinum" . which Malpighi at any rate 

 ; knew, is produced bjr tissue outgrowth, not by hypertrophy 



of the epidermal cells. Concerning the galls described by 

 Malpighi, compare Massalongo, Le galle nell, Anatome Pl. 

 di. M, Malpighi Malpighia, 1^98, Vol. XII, p. 10, and v. 

 Schlechtendal, Melplghi's Abhandl. de variis plantaT^m tu- 

 moribus et excrescenciiis, Bot, Zeitg, , 1866, Bd, XII^, 

 p* 217, 



3. Persoon, Tentamen dispos. method, fungorum, 1798, p. 43. 



4. Link (Berl. Mag. laturf, Fr., 1809, p, 21) distin- 

 guished between Erineum Pers. and Rubigo n. sp. Fries, 

 (Observ. mycol. 1816, T. I, P. 217, Syst. mycol. 1829, T. 

 Ill, p. 520) distinguished three general, Taphria, Erineum, 

 and Phyllerium, which he united into Phylleriaceae. Per^ 

 soon himself later (Mycol. europ, , T, II, p. 2) named ^ 

 Phyllerium, Grumaria (Rubigo Lk.) a»d Taphria as subdivi- 

 sions of his geiius Erineum. Schlechtendal (Denkschr. Bot. 

 Gea.. Regensburg, 1822. p. 73) and Kunze, (Mycol. Hefte II, 

 Leipzig, 1823, p. 133j furnished further investigations 

 from the same standpoint as that of the above named authors, 



5. Die Exantheme der Pfl. und einige mit diesen ver- 

 wandte Krankheiten der Gewaeh^e pathogenetisch und noso- 

 graphisch dargestellt. Wien 1833, p. 376. Meyen (Pflanzaa- 

 pathologie, 1841, p. 242.) later expressed himself as did 

 Unger, concerning the nature of Erineum. 



6, Fee, Men. s. 1, groupe des Phylleriacees. Paris et 

 Strasbourg, 1834. 



