NAH< i.U'tt M. ,-,17 



become coated with eonidia and assume a leaden gr< \ colour, 

 so that in many eases only the points remain green. Finally 

 the attacked leaves die and dry up. 



4. SKCT. I)IITY<IS|-,,K A K. 

 1 . >'/ <!,.<, , >. Mi ,-,-,,,,, ,,,. , 



The forms included under genera of this -roup (e.-j. ,y 

 <lf*iiiin,n and <..'<>ninf]i>riii m ) ha\e as yet heeii little investigated 

 in regard to their parasitie nature. 



2. Siili.-,-t. Macron 



Macrosporium. 



('onidia u'i'ey, muriform, and l>orne on the apex of .-imple or 

 hranehed conidiophores. 



Macrosporium sarcinaeforme Cav. 1 t'avara describes a 

 In-owning and death of a whole field of red elover (Trifolium 

 pratense), and aserilies it to this fungus. Minnie spot- were 

 produced, at first light-coloured, then In-own, finallv eoalesejn..- 



i 



80 a.s to cause- drying-lip of the whole leaf. The short thick 

 eonidiophores were developed on the lower surface of the leaf, 

 and n'ave off pluricellular terminal eonidia. 



M. solani Mil. et Mart. This is deserihed- as oecurriii" almi" 

 with the " black-rot " of the tomato in the I'nited Sta' It i- 



said to cause a rot in the fruit and a leaf-l>li"ht mi hoth t'>mato 



and potato. Ah'ii- with this species there al-o oeelir a /' mm 



(\>. '<-(>) and frequently a < 'Imln.^i,, ////, \ -.^ yet the iclation-hips 

 of the diltei-eiit forms, and the part they take m causing the 

 diseases a-erihed to them, is Imt imperfectly in\e-t i'jaied. 



Soraiier :; ascribes a disease on the potato in (crmany in this 



species or to an Ali>m<n-ni {A. xn//////). He also believes that 



it H the cause of the "early hli-ht " of American potato crops, 



hut furl her investigation is still required. 



Many other species "f .I/'"/-,-/'"''"'"' ha\e lieeii de-i'iihed on 

 plants of economic importance, \et most of them OCCUl "id\ "ii 

 Jiarts somewhat faded or languid, SO that they eaiinm 1- .le ( | 



I'.iin-i .mil Cavarft, /'"////(/ partuit., \. 



/.' ' of th Section /' 1 ' 1888, U.S. D - "i 



A^rii-iiltin e. 



/. >' -,< hi'ilt I . I'fl'i, ' n, 



