130 A FUNGOID CUCUMBER DISEASE IN ESSEX. 



citvina on the bank of the little stream behind the " Robin Hood " 

 Inn. I have made a drawing of this very interesting species, 

 which I understand will be placed along with the illustrations of 

 other Poorest fungi in the Epping Forest Museum. 



A FUNGOID CUCUMBER DISEASE IN ESSEX. 



By M. C. COOKE, M.A., LL.D., .\.L.S., &:c. 



It is now five years since I received from Totteridge leaves of 

 Melon which were affected with a new form of Fungus disease, 

 and this was described in the Gavdenevs' Chronicle for the 5th 

 September, 1896, under the name of Cevcospova nielonis. 



During the past month (September, igoi) I have had 

 leaves of Cucumber sent to me from Chelmsford, affected with 

 the same disease, and although my query to the sender has never 

 been answered, I presume that the locality is Essex, if it is not 

 really Chelmsford, and therefore comes within the limits of the 

 Essex Field Club. 



The leaves are spotted with distinct circular bleached spots, 

 of a pale ochre colour, and about half an inch in diameter. Such 

 spots are brittle and soon break out and fall away, the tissues 

 being quite dead. The dead tissue is traversed by a plentiful 

 mycelium, from which arise darkish olive threads or hyphce, 

 which are unbranched and septate, al)out 150 mm. long. These 

 hyphae bear long conidia, which are almost cylindrical, slightly 

 attenuated upwards, obtuse at the extremities, a little curved, 

 and at first multi-nucleate, ultimately five to seven-septate, faintly 

 coloured, from 80 to 120 mm. long and about 7 mm. thick. 



This fungus belongs to the Black Moulds, and most of the 

 species are parasitic upon, and destructive to living plants. As 

 the disease is truly endophytic and is established within the 

 tissues before the spots appear, there are grave doubts whether 

 there is any hope of cure. x\ll that can be done is to prevent its 

 spreading by destroying the infected plants. 



