HYMENOMY< ETES. 



any sporophores and applying tar t<> the \vi.iunl, while 

 sterns in the forest should In- felled. Immediate artificial 

 closure of wounds in the wood is a very effective preventive 

 measure. 1 



The Hymenoiuycetes arc- divided into 7'///. ,//,//,//,. /.' 

 diaceae, /////"/> ni;,n (included 1>\ I'.refeld in the '/'<////> ///// 

 Tlnhjilini-fnf, Clavarieae, //////"". I',,/,//,,,,-"" , and Agaricii 

 All contain parasitic specie-. 



EXOBASIDIACEAE. 



Exobasidium. 



'I'll-- hasidia are funned uii the extivinit ies uf liranche- 

 the mycelium, \vlliell luvak out through the cuticle of attacked 

 oruan-. The mycelium li\e- in-ide the host -plant . and indin - 

 con>ideral>le malformation. The liasidia emei'-e on the sun 

 of the host (similarly to the ;\<c\ of the J-J">"*<i), and from 

 each of the four >t eri-mata a single spore is ^iven off. 



Exobasidium vaccinii Wor.- (I'.ritain and U.S. Amen, 

 Tlii- is the cause of a very common and conspicuous deformation 

 which affects the leaves, tlu\\ers. and -houts uf Vaecinium l'/V/\. 

 Iiliixi I l-'i-. L'-'iI). I.ca\es, \\hcie alfected, liccoine thicken,-,] 

 and form inv-ular Misters vaulted towards the lower Surface 

 uf the leaf. >u that the lower epidermis covers the convex 

 side and the upper epidermi> line-, the concavity. ( 'hlurophyll 

 is al'-ent in the swollen tissues, hut \\h>Tc Mi.-ters ai'e t-\]iused 

 to direct liuht a hriuht red cell-saj> is developed. 1'art- of 

 the l.-al adjoinin_r diseased -pots may remain normal and 

 ii. Flowers oi' their parts undergo similar niallormat ion : 

 t \\i-s In-come more or less thickened ami twisted, their chloro- 

 phyll disappear-, and a reddish cell-sap is produced. On -udi 

 di-ea-ed place- spores are piodiiced duriliu the -umiiicr. afl.-l 

 wliieh the jiourly developed tissues dr\ up and \\ither. 



\\'hel| thi> fllll-lls is pre-ellt ill tile yollll^ tlSSUBi of il- 

 ho-t-, it eXertS a \erV marked illllllelice 0)1 thcil' de\elopn)clll 



The palisade cells of the leaf l.ecome enlarged, \\liile then 

 chlorophyll almost wholly disappears, and i- replaced Ky a red 



' l-'m t In- 1 , 1 1- 1. -ills mi t liis 1 1, n MI li;i\ ,- ill i < -,i,ls been given, General put. p. 7-. 

 -' \\',,riiniii. \'> rlniiiil . 'I. ntUvrfo . Freiburg, l^ti7: s\ith .'> p 

 '/"'., sin.. is^;i \\.ikUii. /' ../-// ///I'- ./,i/u /!/. -/I. i 



