452 FETCH : 



incorrect identifications of tropical fungi, the diseases of the 

 same plant in different countries are considered quite distinct, 

 and thus the work of a mycologist in one country is thought 

 to be inapphcable to the diseases of another. In actual fact, 

 it is being abundantly demonstrated that plant diseases are 

 identical throughout the tropics, but this state of things has not 

 yet been hitherto perceived for the reasons already mentioned. 

 Even in the same country, an erroneous determination of a 

 known species is hable to cause serious alarm. In the West 

 Indies, for example, the Diplodia on cacao has long been 

 known under the name of Diplodia cacaoicola. But quite 

 recently, in ignorance of the fact that it was the same thing, 

 a scare has been raised by the discovery on cacao of a Lasio- 

 diplodia to whose agency diseases of all descriptions have been 

 attributed. 



The distinctions between the various subdivisions of the 

 Sphserioidacese-Phaeodidymae are by no means clearly 

 understood. Brick {loc. cit.) states : " The genus Botryo- 

 diplodia Sacc. differs from Lasiodiplodia EU. & Ev. in the 

 absence of the paraphyses in the hymenium." This is 

 scarcely correct. The distinguishing iesbtures oi Lasiodiplodia, 

 as given by its authors, are three, viz., the formation of a 

 stroma, the presence of paraphyses, and the weft of hyphse 

 surrounding the stroma ; and would appear from the name 

 that the latter character was considered the most important. 

 EUis and Everhart have erred in laying special stress on the 

 occurrence of paraphyses. The presence of paraphyses alone 

 has never been considered a subgeneric character, either 

 before or after the institution of Lasiodiplodia. Thus, we 

 have, prior to Lasiodiplodia, Diplodia cococarpa Sacc, D. 

 nematospora Sacc, D. cactorum Speg., D. gongrogena Temrae., 

 D. guaranitica Speg. , D. nutans Speg. , D. cegyptiaca F. Tassi . 

 D. paraphysaria Sacc. ; and subsequently, D. paraphysata 

 Ell. & Ev., D. zeylanica¥. Tassi, D. arihrophylli Penz. & Sacc, 

 D. MangifercB Koorders, D. Wurthii Koorders, D. cinchoncB 

 Koorders, Chcetodiplodia coffece Zimm., Ghcetodiplodia vanillce 

 Zimm., all with long paraphyses. Of these, Diplodia para- 

 physata EUis & Everhart is most instructive : it was described 

 in 1897, a year after Lasiodiplodia tubericola EU. & Ev. ; 



