350 INTRODUCTION TO BOTANY 



Gynaecium (female household). The pistil, or collectively the pistils, 

 of a flower. 



Halophyte. A plant which can thrive in saline soil, as that of "alkali " 

 lands or salt marshes. 



Haustorium (drinking organs) ; pi. haustoria. The absorbing organs 

 of some parasites. 



Heliotropism (turning to light). Tendency of plants to turn toward 

 the sun. 



Heterogamy (unlike gametes). The condition of plants whose pairing 

 gametes are dissimilar. 



Heterogamous. Pertaining to heterogamy. 



Heterospory (unlike spores). The condition in plants which produce 

 two kinds of asexual spores. 



Heterosporous. Pertaining to heterospory. 



Homospory (similar spores). The condition in plants which produce 

 but one kind of asexual spore. 



Homosporous. Pertaining to homospory. 



Host. The plant upon or within which parasitic plants or animals 

 develop, and from which they obtain nourishment. 



Hybrid. A plant which is the offspring of an egg of one species fer- 

 tilized by the pollen of another species. The term is also used for crosses 

 between two varieties of plants. 



Hydrophyte (water plant). A plant thriving only in water or marshes. 



Hygroscopic (moisture seeking). Having an avidity for water. 



Hymenium (a membrane). In fungi, a surface layer of interwoven 

 filaments from which the spore-bearing filaments arise. 



Hypha (a web) ; pi. hyphae. The slender vegetative filaments of fungi 

 which may or may not be woven into a mat (mycelium) or a definitely 

 organized plant. 



Hypocotyl. The short stem of an embryo seed plant. 



Hypodermis (under the skin). The tissues which lie immediately 

 beneath the epidermis and which serve to strengthen it. 



Hypogynous (being under the ovary). Applied to those flowers whose 

 stamens and floral envelopes are at the base of the ovary. 



Indehiscent. Not dehiscent, or not splitting regularly. 



Indusium (covering) ; pi. indusia. In ferns, a cellular outgrowth of 

 the leaf covering the clusters of sporangia (sort). 



Inflorescence (flowering). The arrangement of flowers ; or the flower- 

 ing portion of a plant. 



Integument (covering). The covering of the ovule. 



Intercellular. Between or among the cells. 



Internode. The part of a stem between two nodes or joints. 



Intine (on the inside). The inner coat of a pollen grain. 



