286 



Practical Plant Biology. 



Pcnicillium glaucum, sterigniata of, 99. 



tartaric acid changed by, 101. 



Peptide linkage, 17. 

 Perianth, 246. 



Pericycle, 151, 155, 223, 241. 

 Peristomium, 141. 

 Petals, 230, 246. 

 Petri-dish, 61. ; 

 Phloem. See Bast. 



Photosynthesis (carbon assimilation), 41- 

 47, 69, 78, 85, 107, 116, 124, 142, 157. 



action of chlorophyll in, 45, 46, 47. 

 chloroplast in, 45, 46, 47. 



enzymes entering into, 44. 



formaldehyde in, 44. 



hexoses in, 44. 



hydrogen peroxide in, 44. 



starch formed in, 44. 



sucrose in, 44. 



supplies food and energy to living 



nature, 47, 51. 

 Phototropism of Mucor, 93. 

 Physiological species, 65. 

 Piliferous layer, 241. 

 Pinus silvestris. Lectures XXII., 



XXI1L, XXIV., 179-214 (Figs. 



5i, 5 2 , 53, 54, 55. 56, 57. 58, 



56, 60, 6.1, 62, 63, 64, 65, 66, 



67, 68, 69, 70, 72). 

 air-passages of, 184. 



apex of stem of, 185. 



archegonia of, 207. 



bark of, 198. 



bordered pits of, 193, 194, 195. 



bract-scale of, 205. 



cambium of, 186, 183, 192. 



carpels of, 205. 



conducting tracts of, leaves and 



dwarf shoots, 182, 183. 



development of, 186. 



long shoots, 184. 



cortex of, 184. 



cotyledons of, 209. 



cuticle of, 181, 183. 



dwarf shoots of, 179, 182, 183. 

 embryo of, 209. 



embryo-sac of, 206. 



endodermis of, 182. 

 endosperm of, 206, 207. 



epidermis of, 181. 



fundamental tissue of, 183. 



growth in length of, 185. 



thickness, 186. 



heterospory in, 209. 



integument ( = seed-coat), 206. 

 leaves of, 179. 



life-history of, 209. 



long shoots of, 179, 1 80. 

 - medullary rays of, 184. 



megaspore-germination, 206, 207. 



Pinus silvestris, mesophyll of, 181. 



micropyle of, 206. 



nucellus of, 206. 



oosperm, 208. 



- ova of, 207. 



ovules of, 205. 



pericycle of, 182. 

 - pith of, 184. 



pollen of, 200, 20 1, 202. 

 pollen-cones of, 199. 



pollen-sac of, 200, 201, 202. 



pollen-tube-cell of, 207. 



pollination of, 207. 



primary and secondary tissues of, 



186. 



procambial tracts of, 185. 



protoxylem, stretching of, 192. 



resin passages of, 184. 



root of, structure of, 188, 189. 



root-cap of, 190. 



root-hairs of, 190. 



scale-leaves, 179. 



seeds of, 206, 209. 



seed -cones of, 204. 



sporophylls of, 213. 



spring wood and summer wood, 



187. 



stamen of, 200. 



stomata of, 181. 



strobili of, 213. 



suspensor of, 208. 



tap-roots, 181. 



tracheids in, development of, 193. 

 transfusion-tissue of, 182. 



water, path of, in, 190. 



wing of seed of, 206. 



wood, sections of, 195, 196, 197. 

 zonation in wood of, 188. 



Pits, 106, 124, 149, 182, 193 et seqq., 221, 

 227. 



facilitate passage of water, 227. 

 Plasmolysis, 14, 15, 18. 



Polar nuclei, 234. 

 Pollen, 200, 201, 202. 

 Pollen-cones, 199, 204. 



replace dwarf shoots, 204. 

 Pollen-grains ( = microspores), 200, 201. 



carried to micropyles, 207. 



of Ranunculus, 232, 235. 



of Scilla, 246. 

 Pollen-mother-cells, 231. 



Pollen-sac ( = microsporangium), 200, 



201, 202, 232, 246. 

 Pollen-tube, 211, 235. 

 Pollination of Pinus, 207. 



Ranunculus, 234, 237. 



- Scilla, 247. 

 Polysiphonia fastigiata. Lecture XV., 



113-120 (Figs. 20, 21). 

 alternation of generations in, 120. 



