GLOSSARY 



517 



Imperfect, as applied to flowers, having but one of the two kinds of essential 



organs, as stamens but no pistils, or pistils but no stamens; as applied to 



fungi, the stages or forms other than the perfect, 145, 288. 

 Incumbent, as applied to stamens, the same as introrse, 158. 

 Indehiscent, remaining closed, 206-208. 

 Indeterminate, applied to shoots which grow throughout the season without 



forming a resting bud; to flower shoots where the main shoot is not 



terminated by a flower, 55, 148. 

 Indusium (In-du'-si-um), a membranous structure covering and protecting 



the sorus in many ferns, 361. 



Inferior, said of the pistil when it is joined to the calyx, 147. 

 Inflorescence, the manner of arrangement of flowers on the shoots, 148. 

 Integument, a covering, applied to the outer layers of the ovule which form 



the seed coats or testa of the seed, 200-202, 204, 393, 400, 414-416. 

 Introrse, said of anthers attached by the outer face to the filament so that 



the anther faces toward the axis of the flower; same as incumbent, 



158. 

 Involucre (In-vo-lu'-cre), a whorl of bracts or small leaves just below the 



flower, it may be green, or otherwise colored, 167. 

 Irregular, said of flowers when the members of any series, as petals or 



sepals, are unequal in size or shape, 146. 

 Labellum (La-bel'-lum), a lip; in the orchids the peculiar sac-like petals 



of the flower, 188, 189. 

 Labiate, lipped, 146. 



Lamella (plural, lamellae), name applied to the gills of mushrooms, 323. 

 Legume, a dry fruit of a single carpel splitting along both edges or sutures, 



a true pod, 24, 165. 



Lenticels, the openings in the bark of young woody stems for the inter- 

 change of gases, 73, 120. 



Leucoplast (Leu'-co-plast), a colorless plastid, 92. 

 Life cycle, the complete cycle, or history, of forms appearing in the life 



of a plant, 238, 239, 244, 320, 355, 372, 404, 422. 

 Ligulate, strap-shaped, said of a gamopetalous corolla open down one 



side and spread out in the form of a short strap, 146. 

 Ligule, the membranous outgrowth on the leaves of grasses at the junction 



of the sheath and blade; or at the junction of the blade and spore case 



in Isoetes, 57, 78. 

 Lipase, an enzyme formed by plants which dissolves oil products stored 



for food, 133. 

 Locule, a cavity of an ovary or anther, 144, 147, 155, 158, 160, 165, 173, 



174, 181. 

 Loculicidal, splitting into the cavity of a locule along the back of the 



carpel, 208. 



