Hypanthium. A cup-shaped enlargement of the receptacle on which the calyx, 

 corolla, and often the stamens are inserted; in perigyny the "calyx tube". 



Hypogeous. Occurring below the surface of the ground. 



Hypogynium. The perianthlike structure subtending the ovary in some genera of 

 the Cyperaceae. 



Hypogynous. Said of flowers in which the perianth and stamens are inserted upon 

 the receptacle below the gynoecium. 



Imbricated. Said of organs that are so placed as to overlap like the shingles on a 

 roof (fig. 741). 



Immersed. Growing under water. 



Imperfect flower. Having either stamens or pistils, but not both. 



Incised. Having the margin deeply cleft. 



Included. Not projecting beyond (an enclosing part of the plant); said of an 

 inner structure of a flower relative to an outer structure when the inner struc- 

 ture does not extend beyond the outer one or beyond some specified part of 

 the outer one; for example, of stamens included in the corolla tube (fig. 650). 



Incrassate. Made thick or stout, as the leaves of some species of Sedum. 



Incumbent. Lying upon anything; said of cotyledons when the back of one rests 

 against the stalk of the embryo. 



Indehiscent. Said of fruits that remain closed and do not shed their seeds. 



Indeterminate. Said of inflorescences in which the terminal flowers open last; also 

 said of conditions in which growth and differentiation are not arrested. 



Indurate. Hardened and thereby often persistent. 



Indusium. The scale-like covering that invests the sorus in ferns. 



Inferior. Occurring below; said of the ovary when it occurs in such a manner as 

 to appear to be below the other flower parts (fig. 3b). 



Inflated. Hollow and swollen in a manner to appear as if distended with air. 



Inflorescence. An aggregation of flowers occurring clustered together in a particu- 

 lar manner which is usually characteristic of a given kind of plant (fig. 788). 



Infrastamineal. Below the stamens. 



Infrastipular. Below the stipules. 



Infructescence. The inflorescence in a fruiting stage; collective fruits. 



Insectivorous. Consuming insects, i.e., by digesting out the organic parts. 



Insertion. The place of attachment of one structure on another, 



Interlacunar. Between air spaces. 



Internode. The part of a stem between any two adjacent nodes. 



Introgression. Entrance; going in; used for hybridization and repeated back-cross- 

 ing which can result in genetic contamination of one taxon by another. Intro- 

 gressant: that which goes in; used for the organisms which show the results of 

 introgression. 



Introrse. Turned inward, toward the axis. 



Involucel. A secondary involucre, such as one subtending an umbellet in a com- 

 pound umbel, (fig. 788). 



Involucre. A group of closely placed, free or united bracts that subtend or en- 

 close an inflorescence (fig. 788). 



Involute. Said of margins that are rolled inward (toward the adaxial side), as in 

 a petal or a leaf. 



Irregular. Said of the members of a given kind of structure when they are unlike 

 in shape or size, such as the unequal lobes of a corolla (fig. 3b). 



Joint. The internode of a grass culm; an articulation, as in fruits of Desmodium. 



(fig. 82c). 

 Jointed. Having one or more constrictions marking a point of articulation (fig. 



420b). 



1718 



