14 



It has not yet been ascertained whether the disease which exists 

 in many parts of the Island is in all cases identical with that dis- 

 covered at the Gardens, but it is clearly sheAvn that Ave have with us 

 a destructive pest which care and attention alone can eradicate, and it 

 is quite probable that the other districts may be affected by one or 

 more similar destructive diseases — but this requires further obser- 

 vation. 



J. H. HART, F.L.S., 

 Supt. Royal Botanic Gardens. 



12th September, 1894. 



Botanical Department, Trinidai). — Circular Note No. 11. 



During the year 1893 one of the experiments carried on in 

 connection with the investigation of Sugar Cane Disease consisted of 

 infecting a healthy growing Cane plant with the microconidia of 

 Tricliosplioeria Sacchari, Massee. 



The Cane selected Avas a healthy stem in which no borer or other 

 insect enemies Avere present, and the system of inoculation adopted 

 AA'as simply to insert the spores into broken surfaces made for the 

 purpose in the midrib of the leaf. 



The Cane continued to groAv apparently unaffected for some time, 

 and eventually reached some six feet in length, but it gradually 

 assumed on unhealthy appearance, lost its leaves and dried away into 

 a shrivelled condition. In this state it AA^as sent to Kcav and the 

 report on the specimen is appended hereto. It proves, on the spot' 

 that the Fungus is 'capable of totally destroying a cane Avithout the 

 aid of insect agency of any kind. 



"Diseased Sugar Caxe from Trinidad. — Communicated by Mr. J. H. 

 "Hart, August, 1894. 



" The folloAving phases in the life cycle of Trichosphceria Sacchari are present 

 "in the cane. 



"Conidial Conditions — 1. Melanconium stage. 



2. Macroconidial stage. 



3. Colletotrichum stage. 



" Ascigerous Condition. — In small quantity and accompanying it, perithecia 

 "formed of purple polygonal tissue and enclosing large brown. 1 — septate spores 

 "not produced in asci — or stylospores. These structures have also been observed 

 "united Avith the ascigerous form on canes sent from Barbados by Mr. Barber 

 "and complete the usual sequence of phases in the life cycle of species allied to 

 ' ' Trichosphceria Sacchari. " 



J. H. Hart, F.L.S. 

 13th September, 1894 



