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Glossary 



Hymenium. A spore-bearing layer of hyphae. 



Hy-pertro-phy. An abnormal enlargement or excessive growth of particular parts, 

 which may be caused by excess of nourishment or induced by parasites. 



Hy-pha. A tubular thread-like cellular structure, collectively constituting the vege- 

 tative body or mycelium of the fungus. 



Hy-po-phyllous. Growing on the under surface of a leaf. 



Indigenous. Native to a country, and not introduced. 



Intercellular. Between the cells of the host-plant. 



Intracellular. Within the cells of the host-plant. 



Laciniate. Cut up into narrow lobes. 



Lumen. The cavity bounded by the walls of an organ. 



Mesos-pore. A single-celled spcre-form related to the teleutospore, and probably 

 representing a transition from the unicellular Uromyces. 



Micron or 'Micromillimetre. Indicated by the sign p, is the standard unit for 

 microscopical measurements, and equals i-ioooth of a millimetre, or i-25,oooth 

 of an inch. 



Mutation. That kind of variation produced by internal influences, in which the 

 equilibrium of the organism is disturbed and a new position of equilibrium 

 found strikingly different from the original one, sometim-es called spontaneous 

 variation. , 



Mycelium. The vegetative portion of a fungus composed of one or more hyphae. 



Nucleus. An organized proteid constituent of the cell, necessary for its continued 

 growth and life. 



Obligate parasite. One in which a parasitic mode of life is indispensable for com- 

 plete development. 



Orbicular. Applied to a flat body with a circular outline. 



Papillate. Covered with protuberances or terminating in a papilla. 



Paralyses. Barren filaments associated with the spores, either slender or variously 

 swollen, hyaline or coloured. 



Parasite. An organism living on r,r in another living organism, and at its expense. 



Pedicel. Spore-bearing stalk. 



Persistent. Lasting, not soon falling away, applied to the pedicel of a spore. 



Firifcrm. Pear-shaped. 



Plasmodium. A mass of naked protoplasm, containing many nuclei and exhibiting 

 movement. 



Plurivorous. Applied to a parasite which can exist on a variety of host-plants. 



Predisposition. The tendency to disease exhibited by an organism when the con- 

 ditions are favorable to the development of the parasite. 



Primordia. The beginnings of any structure, such as the aecidium. 



Promycelial S'pore. The spore produced by a promycelium, also known as a sporid- 

 iolum. 



Promycelium. The short germ-tube of a teleutospore, which produces a few spores 

 unlike the teleutospores, and then perishes. 



Protomycelium. A term used by Eriksson to denote the early plasmodia-like stage 

 of the mycelium in certain Rusts. 



Protoplasm. The living substance in plants, consisting of albuminoid matter. 



Pseudo-parenchyma. False tissue or compact mycelium, so called because it is 

 formed by the union of previously separate elements or hyphae into a dense 

 mass, while true tissue is derived from a single cell, which divides and 

 forms a coherent, more or less firm, mass of cells. 



Pseudo--peridium. The outer envelope of the aecidium, consisting of sterile cells. 



Pulverulent. Powdery 



Pul-vinate. Cushion-shaped. 



Reticulate. Covered with lines or ridges crossing each other so as to form a net- 

 work. 



Saccate. Bag-shaped. 



Sa-pro-phyte. A fungus which preys upon dead organic matter only, in contrast to 

 a parasite. 



Se-ptate. Partitioned off into distinct divisions. 



Sorus. A cluster of spores constituting a spore-bed, as uredosorus, teleutosorus. 



