278 GLOSSAEY AND INDEX. 



legume, a dry fruit consisting of one carpel, opening by both dorsal and 



ventral sutures. 

 lignified, converted into wood, 45. 

 lenticels, lenticular formations of cork under stomata on young woody 



shoots, 248. 

 ligulate, strap-shaped, as the ray flowers of the Compositse ; having a 



ligule, as the leaves of grasses, 158, 257. 

 ligule, the membranaceous appendage at the top of the leaf-sheath of 



grasses ; the strap-shaped corolla of many flowers of the Compositae, 



158, 161, 257. 

 linear, narrow and elongated, 58. 

 lodicule, one of the two, rarely three, scale-like bodies occurring in the 



flowers of grasses. Apparently they are the rudiments of floral en- 

 velopes, 159. 



macrosporangium, a sporangium containing macrospores, 142. 



macrospore, a large archegonia-bearing spore, such as those produced by 

 Selaginella, etc., 143, 146. 



medullary, pertaining to, or of the nature of, the medulla or pith. The 

 primary medullary rays are parts of the fundamental tissue of a stem 

 forming vertical plates between the fibro-vascular bundles, and radi- 

 ating from the pith outwards. In perennial dicotyledonous stems 

 secondary rays of similar character start from the cambium each 

 spring, 39. 



mericarp, one of the two halves, or carpels, into which the ripe fruit of 

 the maple and of umbelliferous plants separates, 89, 225. 



mesocarp, middle layer of the pericarp, 92. 



micropyle, the minute opening at the apex of the ovule through which 

 the pollen-tube penetrates. In the seed it is more or less completely 

 closed, 2, 78. 



microsporangium, a sporangium containing njicrospores, 142. 



microspore, a small, male spore, 143, 146. 



midrib, the large middle rib, or vein, of a leaf. 



monadelphous, having the filaments united in a ring or cylinder around 

 the pistil, as in mallows, etc., 198, 214. 



moniliform, contracted at intervals, so as to resemble a string of 

 beads, 35. 



monocotyledonous, having one cotyledon ; belonging to the class of 

 flowering plants characterized by having an embryo with one coty- 

 ledon, parallel-veined leaves, stem with scattered and closed fibro- 

 vascular bundles, and fiowers commonly on the plan of three. 



monqecious, having separate staminate and pistillate flowers on the same 

 plant, 86. 



