INTRODUCTION. 



SEGREGATE (from segregatus, separated). Each floret EQUISETACE.E, Horsetails. Example, Equisetum. Third, 



having its own peculiar in volucrum. LYCOPODINE^:, Club-mosses. Example, Lycopodium. 



The 23rd class, POLYGAMIA, contains two orders, Fourth, MARSILEACE^E. Examples, Isoetes and Pilularia. 



formed exactly on the same principles as the 21st and Fifth, Musci, Mosses. Examples, Phascum Hypnum, &c. 



22nd classes, called MON<ECIA and DIOZCIA. Sixth, HEPATIC^;. Examples, Jangermannia and Mar- 



The 24th class, CRYPTOGAMIA, contains nine orders, chantia. Seventh, ALG^E, Sea-weeds. Examples, Exil- 



chiefly formed from the reproductive organs, which it is un- aria, Nostoc, Conferva, Viva, Spharococcus, Fucus, &c. 



necessary to describe here further than to give the names Eighth, LICHENES. Example, Lichens, Ninth, FUNGI. 



and examples. First, FILICES, Ferns. Examples, Polypo- Examples, Agaricus, Clavaria, Morchella, Peziza, Sph<e- 



tllum, Osmunda, Aneimia, Ophioglossum, &c. Second, ria, &c. 



GENERAL MANAGEMENT OF PLANTS GROWN UNDER GLASS. 



Although we have given an account of the propagation and culture of the various GENERA in the 

 body of the work, we think it expedient to describe the general management of ornamental plants 

 grown under glass, such as greenhouse, stove, or hothouse, as well as alpine plants. 



1. Alpine plants are such as will not grow in the open ground to any perfection, and must 

 be protected during winter by a frame ; they are mostly natives of high situations, among rocks 

 and on the tops of mountains, and consequently of low growth, seldom, if ever, exceeding six inches. 

 They should be grown in small pots, and will all thrive well in a mixture of loam, peat, and sand, the 

 pots to be always well drained with potsherds ; they should be shifted at least twice every season, and 

 divided if the plant has grown too large ; the mould which has been shaken from the pots, if not ex- 

 hausted, to be mixed with new earth, and the plants potted afresh, after which they require a little 

 water. If these instructions are attended to, alpine plants will always look healthy and neat. 



2. Greenhouse plants are such as are natives of the Canary Islands, New Holland, and the Cape of 

 Good Hope, and other countries in the same latitudes, which only require to be protected from frost in 

 this country; therefore they are kept under glass during the winter. No fire is requisite, unless 

 a strong frost is expected during the night. In winter they should have plenty of air given them 

 upon fine days, as early in the day as the weather will permit ; the house to be shut up very early 

 in the afternoon, if cold. If the weather continues damp and wet, then a little fire is requisite to 

 expel the damp, as greenhouse plants are more likely to be injured by damp than cold. The plants 

 should be looked over every day, taking off any dead leaves, and watering those that are dry ; this 

 should be done early in the forenoon, and if the surface of the mould in the pots becomes green, it should 

 be removed with a flat stick, but not so deep as to injure the roots, and a little fresh mould laid on 

 instead. Towards spring they require a more plentiful supply of air and water, and when frost is not 

 apprehended some of the sashes should be left a little open all night, and the air gradually admitted as 

 the weather advances towards summer, until the time of setting the plants out of doors : in some seasons 

 this may be about the middle of May, in others not until the end. Calm cloudy weather is the best 

 time for setting them out, when the most sheltered situation should be chosen, where a bed of ashes 

 should be previously prepared for them. There are various opinions as to the best time of shifting 

 greenhouse plants into fresh pots and mould, but we think that the earliest spring time should be pre- 



