NI E 



396 



NO N 



eluding N. tdbacum, the well-known To- 

 bacco. This and nearly all the others 

 are hardy annuals. Seed. Rich light 

 loam. 



NIEREMBERGIA. Four species. 

 Green-house herbaceous, except the 

 hardy annual N. aristata. Seed or cut- 

 tings. Light loam. 



NIGELLA. Fennel flower. Eleven 

 species. Hardy annuals and biennials, 

 except the herbaceous N. coarctata. 

 Seed. Common soil. 



NIGHTSHADE. Solanum. 



NIGHT-SOIL. See Dung. 



NIGHT TEMPERATURE in hot- 

 houses and frames should always ave- 

 rage from 10 to 20 degrees lower than 

 the temperature in which the plants are 

 grown during the day. It is in the night 

 that the individual functions are reno- 

 vated by a temporary repose, and if 

 left to the dictates of healthy nature 



tionably increased by the higher tem- 

 perature. — Principles of Gardening. 



NIPHOBOLUS. Eight species. 

 Stove ferns. Seed and division, Sandy 

 loam and peat. 



NISSOLIA. Seven species. Stove 

 evergreen climbers and shrubs. Cut- 

 tings. Loam and peat. 



NITRATES. See Saline Manures. 



NITTA TREE. Parkin. 



N I V E A . Seven species. Green- 

 house evergreen shrubs. Young cut- 

 tings. Sandy peat and loam. 



NOCCA. Four species. Stove ever- 

 green shrubs. N. latifoUa is half-hardy. 

 Cuttings. Common soil. 



NOCTUA, a genus of moths. The 

 following are injurious to our gar- 

 dens : — 



N. gamma. The Y, or Gamma Moth. 

 The caterpillars of this are very de- 

 structive to pens and other kitchen ve- 

 getables during the summer. Mr. Cur- 



the sap, like the blood, flows at night, tis describes it as "being beset with 



with a much diminished velocity 



That plants do become exhausted by 

 too unremitting excitement, is proved 

 to every gardener who has peach- 

 houses under his rule ; for if the great- 

 est care be not taken to ripen the wood 

 by exposure to the air and light during 

 the summer, no peach tree will be fruit- 

 ful if forced during a second successive 

 winter, but will require a much more 

 increased temperature than at first to 

 excite it even to any advance in vegeta- 

 tion. 



The experiments of Harting and 

 Munter upon vines growing in the open 

 air, and those of Dr. Lindley upon vines 

 in a hot-house, coincide in testifying 

 that this tree grows most during the less 

 light and cooler hours of the twenty- 

 four. But the hours of total darkness 

 were the period when the vine grew 

 slowest. This, observes Dr. Lindley, 

 seems to show the danger of employing 

 a high night temperature, which forces 

 such plants into growing fast at a time 

 when nature bids them repose. 



That the elevation of temperature at 

 night does hurtfully excite plants is 

 proved by the fact, that the branch of a 

 vine kept at that period of the day in 

 temperature not higher than 50°, in- 

 hales from one-sixteenth to one-tenth 

 less oxygen than a similar branch of the 

 same vine during the same night in a 

 temperature of 75'. The exhalation of 

 moisture and carbonic acid is propor- 



greenish hairs, and on the back with 

 yellow or white ones. It has a brown 

 head. When fully grown, which takes 

 place in the course of a few weeks, it 

 forms a while cocoon, and changes into 

 a blackish brown pupa. 



" There are three or four generations 

 of moths during the summer, which ap- 

 pear at intervals between April and 

 October. In the latter month, we have 

 seen them fluttering round flowers at 

 dusk literally by thousands : this remark 

 applies more particularly to the southern 

 counties of England. The wings are 

 about an inch across, the upper ones 

 are varied with grey and brown, having 

 quite a silvery hue, and towards the 

 centre there is a perfect silvery Greek 

 gamma, y, with a rusty spot close be- 

 fore it, the lower wings are pale ashy 

 brown, with the nerves and hinder mar- 

 gin deep brown. There are few reme- 

 dies that can be applied to this pest; 

 perhaps the best of all is hand-picking 

 the caterpillars. — Gard. Chron. 



N. exclamationis. The caterpillar 

 of this moth feeds on the stalks of the 

 potato. 



NOISETTIA /o«g-//"o//a. Stove ever- 

 green shrub. Young cuttings. Light 

 rich soil. 



N O L A N A. Five species. Hardy 

 annual trailers. Seed. Common soil. 



NOLINA georgiana. Hardy herba- 

 ceous. Offsets. Sandy peat. 



NONATELIA. Four species. Stove 



