GLOSSARY AND INDEX. 279 



monopodial, having a continuous main axis on which lateral branches 

 arise aoropetally, i.e. in succession towards the growing point, the 

 common mode of branching in higher plants ; opposed to dichotomy, 

 in which the terminal bud regularly divides into two ; and to sympo- 

 dium, in which the axis is made up of a series of regularly super- 

 posed lateral growths, the terminal bud being crowded to one side 

 each time. 



morphology, the doctrine of form ; that branch of biological science 

 which endeavors to ascertain the origin and follow the developmental 

 history of existing forms of plants and animals. 



mother-cell, any cell from which one or more new ones (called daughter- 

 cells) arise, 134. 



multiplication, 82. 



mycelium, the vegetative part of a fungus composed of hyphss, 112, 116. 



napiform, turnip-shaped, 35. 



nectary, the part of a flower or other organ that secretes nectar, i.e. the 

 sweet substance from which honey is made, 76. 



node, one of the joints of a stem from which leaves arise. 



nucellus, the central mass of an ovule ; a tissue within which the embryo- 

 sac is developed and which is subsequently absorbed or remains as 

 perisperm, 78. 



nucleolus (pi. nucleoli), a body enclosed in the nucleus and distinguished 

 by its different refractive power and deportment towards reagents, 

 101: 



nucleus (pi. nuclei), a body, largely proteinaceous and of complex struc- 

 ture, forming an essential part of the living cell, and playing an im- 

 portant role in cell-division and reproduction, 101. 



numerical plan, the fundamental plan or number exhibited by the dif- 

 ferent whorls of the same flower. The numerical plan of monocoty- 

 ledons is commonly three, that of dicotyledons five, 74. 



nut, a hard or leathery indehiscent fruit, especially of various trees and 

 shrubs, having the seed free from the pericarp. 



nutlet, a small nut, such as the so-called achenium of the crowfoot, etc. 



oblanceolate, reversed lanceolate, 58. 



oblong, two or three times as long as broad, the sides approximately 



parallel, 58. 

 obovate, reversed ovate, 58. 

 offset, a short branch that takes root, and thus gives rise to a new 



plant, 258. 

 oil, 7, 18. 



