Transactions of the London Horticultural Society. 363 



2568. EULO^PHIA [Eot. reg. 1972. 



*inacrostSchya Lindl. long-spiked A 23 e.l 2 jn.d Y. spotted with R Ceylon 1836 R p.l 



" A handsome species of this extensive genus, inabiting shady 

 woods in Ceylon, whence it was sent to the Horticultural So- 

 ciety some years ago, by Mr. Watson, the superintendent of 

 the Botanical Garden at Peradenia. It is one of the easiest of 

 orchidaceous plants to cultivate, and produces its graceful 

 racemes of green and yellow flowers abundantly towards the 

 latter part of the year. They go on growing and producing 

 fresh flowers till Christmas." [Bot. Reg., July.) 



Orchiddcece § Epidhidrece. 



Hartwegm. A new genus of Mexican Orchidaceee, received 

 by the Horticultural Society from the neighbourhood of Vera 

 Cruz, where it was found by Mr, Theodore Hartweg, after 

 whom, as the original Hartweg/a proves to be nothing but 

 Chlorophyllum, Dr. Lindley has named it. 



REVIEWS. 



Art I. 2^ransaclions of the Horticultural Societij of London, Second 

 Series. Vol. I. Part V. 4to. London, 1833. 



{Continued from "Vol. XII. p. 436.) 



53. On the Culture of the Potato. By T. A. Knight, Esq., F.R.S., 

 President. Read March 19. 1833. 



" I HAVE SO often addressed communications to this Society upon the 

 culture of the potato, that many of its members may not improbably think 

 that more than a sufficient extent of the pages of our transactions have been 

 already devoted to that subject. It would certainly not be difficult to find 

 one more entertaining ; but, if the farmer can be made to derive such inform- 

 ation from our tran.sactions as will enable him to cause the same space of 

 ground which now affords one bushel of potatoes to afford two, and the 

 peasant to cause the half acre, which now supplies his table with potatoes, 

 to afford him in addition a considerable weight of animal food, few subjects 

 can be more important ; and, therefore, conceiving myself to be prepared to 

 communicate some further useful information, I venture to address another 

 communication upon the same subject. 



" The fact that every variety of potato, when it has been long propagated 

 from parts of its tuberous roots, becomes less productive, is, I believe, un- 

 questionable. I have often witnessed the progressive decay of vigour and the 

 different effects of the influence of age, upon many different varieties. The 

 quality of some has remained perfectly good, after the produce in quantity 

 has become highly defective ; whilst in others that has disappeared with the 

 vigour of the plant. I brought to this place a single tuber of Lankmann's 

 potato soon after that was imported : the produce of that variety was then, 

 and continued during some successive years, very great; but its vigour was 

 gradually diminished ; and in the last year its produce was at least one third 

 (more than seven tons per acre) less than I obtained from the same soil, and 

 under, in every respect, the same management, from other varieties of nearly 

 similai' habits, but which had recently sprung from seed. The propagation 

 of expended varieties, therefore, appears to me to be one of the causes why 

 the ci'ops of potatoes generally have been found so much less than those 



