GLOSSARY 385 
HOST : a plant or animal attacked by a parasite. 
HYPHA : an individual filament of a mycelium. 
HYPOCOTYL : the axis of the embryo sporophyte between the root-tip 
and the cotyledons. 
HYPOGYNOUS : applied to a flower whose outer parts arise from beneath 
the ovary. 
INFLORESCENCE : a flower-cluster. 
INTEGUMENT : in Spermatophytes a membrane investing the nucellus. 
ISOGAMOUS: applied to plants whose pairing gametes are similar. 
MALE CELL : in Spermatophytes the fertilizing cell conducted by the 
pollen-tube to the egg. 
MEGASPORANGIUM : a sporangium which produces only megaspores. 
MEGASPORE : in heterosporous plants the large spore which produces a 
female gametophyte. 
MEGASPOROPHYLL : a sporophyll which produces only megasporangia. 
MESOPHYLL : the tissue of a leaf between the two epidermal layers which 
usually contains chloroplasts. 
MICROSPORANGIUM : a sporangium which produces only microspores. 
MICROSPORE : in heterosporous plants the small spore which produces a 
male gametophyte. 
MICROSPOROPHYLL : a sporophyll which produces only microsporangia. 
MICROPYLE : the passageway to the nucellus left by the integument. 
MONCECIOUS : applied to plants in which the two sex organs are upon 
the same individual. 
MYCELIUM : the mat of filaments which composes the working body of 
a fungus. 
NAKED FLOWER : one with no floral leaves. 
NUCELLUS : the main body of the ovule. 
OOGONIUM: the female, egg-producing organ of Thallophytes. 
OOSPHERE : the female gamete, or egg. 
OOSPORE : the sexual spore resulting from fertilization. 
OVARY : in Angiosperms the bulbous part of the pistil, which contains 
the ovules. 
OVULE : the megasporangium of Spermatophytes. 
PARASITE : a plant which obtains food by attacking living plants or 
animals. 
PERIANTH : the set of floral leaves when not differentiated into calyx 
and corolla. 
