58 THE GARDENER. [Feb. 



and 40 to 50 feet in length, is heated sufficiently by a flow and return 

 pipe passing round it under the side benches. Or in other words, a 

 house in which these plants may be grown perfectly, requires no more 

 piping than is considered necessary for heating an ordinary greenhouse. 

 The benches should be of slate, on supports of either iron or wood, the 

 former being preferable on account of its durability. These benches 

 should be covered either with Derbyshire spar, or cannel-coal broken 

 up into small nodules, upon which the pots can be arranged. Cannel- 

 coal always appears clean, and the dull black colour is not at all con- 

 spicuous, while it efficiently answers every purpose for which spar or 

 shells are used. Most Odontoglots grow freely in a compost of fibrous 

 peat, some dried horse-droijpings, chopped Sphagnum, moss, and sand. 

 The pots must be thoroughly clean and dry, and plenty of drainage must 

 be used, in order that all superfluous moisture may pass away readily. 

 Odontoglots require an abundant supply of moisture when in a healthy 

 growing condition ; but, like other plants, they are injured by stagnant 

 rottenness at the root. We will now glance at those species best worth 

 cultivating for their winter-flowering qualities. 



0. Alexandrce. — This is one of the most beautiful species in the 

 genus, and deservedly popular with Orchid-growers. Its flowers vary 

 from pure white to white suffused with rosy lilac, and heavily blotched 

 on the lip and sepals with brown. A remarkably fine specimen 

 flowered at Meadow Bank some time ago bearing 120 flowers, 56 of 

 which were borne on one spike. I saw many plants of this species 

 growing in a brick pit at Meadow Bank last summer, and they were in 

 very fine condition ; while the expense of cultivation would not be 

 more than that of greenhouse plants in general. This species should 

 be grown by the dozen where there is convenience, as where a good 

 stock is kept, it may be had in bloom throughout the year with but 

 little intermission. Its flowers last a long time in beauty. After 

 potting, this and all other Odontoglots should be surfaced with a 

 layer of fresh green Sphagnum, which not only conceals the compost 

 and gives the pot-tops a clean and fresh appearance, but also maintains 

 an equable state of moisture at the root. 



0. cristatum. — This is not so showy as some species, but highly in- 

 teresting, and worth cultivating for variety in a collection. Its flower, 

 spikes are slender, often branched, and the flowers yellowish, heavily 

 blotched with purplish brown. The crest of the lip is white, and in 

 some varieties a large proportion of the lip is also white. It flowers 

 freely during the winter, and lasts a month or six weeks in perfection. 



0. Cervantesii. — A very pretty dwarf species, often known in gar- 

 dens as O. membranaceum, introduced from Western Mexico in 1845. 

 The plant has small, angular, one-leaved, pseudo-bulbs, and produces a 



