22 NOTICES OF BOOKS AND MEMOIRS. 



to R. affinis, W. & N. It is very abundant in a stone quarry near 

 Berkswell, Warwickshire. I first observed it in August, 1878 ; 

 but I am informed by Prof. Babington that the ^Dlant was found 

 many years since near Atherstone, Warwicksliire, by the bite Eev. 

 Andrew Bloxam, but was seiit bearing a different name to that 

 given above. I have collected a series of siDecimens for the 

 Exchange Club. — James E. Bagnall. 



Extracts anO Notices of 9SooIi!S5 ana iltcmotvs5< 



THE LIFE-HISTORY OF HEMILETA VASTATRIX ON COFFEE. 



[Mr. H. Marshall Ward has presented his thu'd Keport on 

 Coffee-leaf Disease in Ceylon. It contains, as was to be expected, 

 an exhaustive inquiry into the origin and life-history of Hemileia 

 vastatrio, the nature of its relations with the coffee plant, and the 

 effects of remedial measures. The life-history of the Hemileia 

 cannot be better stated than in his own words, which we extract 

 fi'om the section of the Report devoted to it. In our next number 

 his summary of the main points of importance in the whole 

 inquiry wiU be given.] 



** The outcome of numerous observations in addition to and 

 in continuation of those referred to in former reports, shows that 

 the history of the fungus which causes coffee-leaf disease may be 

 fairly stated thus : — 



An orange-coloured papillate spore, or granule of * rust/ 

 taken from a patch on a diseased leaf and sown in a drop of water 

 on the lower surface of a healthy coffee-leaf, soon germinates — i.e., 

 it absorbs water and oxygen, swells up slightly, and protrudes a 

 delicate, thin-walled tube from one or more points of its surface. 

 This tube is a direct continuation of the spore itself, and the granular 

 orange-coloured contents of the latter pass along the cavity of the 

 tube as it extends on the surface of the leaf. On arriving at the 

 orifice of a stoma or * breathing pore,' this germinal tube com- 

 mences to block it up, and soon sends a prolongation through the 

 orifice into the passages between the loosely arranged cells of the 

 interior of the leaf. Once safe inside the leaf, the short tube 

 begins to branch in two or three directions, each branch 

 absorbing the fluid bathing the leaf-cells with wdiicli it is in con- 

 tact. As these first-formed branches gather strength and material, 

 they put forth several other branches which rapidly extend into 

 the spaces between the tissues around, and in this manner is 

 formed a spreading meshwork or mycelium of short, stumpy, fungal 

 tubes. As growth proceeds from the primary tube in all directions 

 around the point of entry, the increasing mycelium soon requires 

 more food than can be obtained by simply absorbing the nutritive 

 fluids bathing the leaf-cells with which the branches are closely in 

 contact ; this increased demand for food is effectually supplied 



