156 Increasitig Plants hy Cuttings^ Sjc. 



on how many circumstances the growth of a cutting depends. I 

 did not succeed in rooting in this way some ericas and bigno- 

 nias, Plumi^rm angustifolia, Cereus columna Trajan/, Vanguiera 

 spec, from Brazil, /Spondias dulcis, Illicium anisatum, Psoralea 

 odoratissima, ^4'ster argophyllus, and some other plants, in which 

 the cause of failure evidently lay in particular or outwardly un- 

 favourable circumstances, which it was as impossible to remedy 

 as it was to make them take root, such as sickly or old shoots, 

 wet and consequent decay. 



2. Leaves and parts of leaves of the following plants were 

 rooted in charcoal. 



It appears very remarkable to me that the peripherous forms 

 of plants should display an extraordinary aptitude and inclina- 

 tion to form roots, so much so that half-leaves of Peiresk/or, Po- 

 lianthes mexicana Zuccar., and leaves of £uph6rbza fastuosa in a 

 short time filled their pots so full of roots that they were obliged 

 to be repotted. 



In from eight to fourteen days : leaves of Cecr6p/«; palmata, 

 O'xalis majidioccdna, O. purpurea, £uph6rbm fastuosa, Cycla- 

 men indicum, Lophospermum scandens, Martynm craniolaria, 

 Begonm monoptera, B. bulbifera, Ipomoe^a superba, I. spec, e 

 Corcovado, Mesembryanthenjum tigrinum, Gesnera latifolia, G. 

 atrosanguinea, Sinningm guttata, Piper peiresk/f^/o/mw, all sorts 

 of Gloxin/a, even calyces and mere flower stems ; pieces of leaves 

 of Convolvulus Batatas, Peireskm grandifolia, Polianthes mexi- 

 cana, and warts of the large-warted mammillaria. 



In three weeks : the tops of the leaves of Agave americana fol. 

 var., leaves of Jacaranda brasiliensis, bundles of leaves of P\- 

 nus excelsa, leaves of Mimosa Houston/, and Cyperu5 vaginatus. 



In five weeks, whole and half-cut folioles of Encephalartos 

 caffer and Zamia integrifolia produced a number of roots from 

 the surface of the cuts. 



Many leaves have not yet made roots, but for a considerable 

 time have formed callosities, such as Z/aurus nitida, Bignon/fl' 

 Telfair/(^, Carolinf-a princeps, Ardisise, Garden/<^, Adanson/a 

 digitata, Dracae^na, &c. As experiments that did not succeed, 

 we may mention portions of the leaves of Amaryllis and Crinum, 

 of ferns, of tropical Orchideae, of Dasylirion and Hecht/a, ^\\~ 

 \andsia, Pandanus, Phormium tenax, of tropical tuberous-rooted 

 ^riiideae, old leaves of the Agave, and some others which, partly 

 through rotting by wet, or other mischances, were prevented 

 from growing. 



It is to be wished, that, roused by this hint, many experiments 

 may be tried with charcoal ashes, as in most cases, when not 

 contrary to nature, I can guarantee success. I shall hereafter 

 take the opportunity of laying before the public, as far as my 

 experience goes, the good effects of charcoal as a cure for sick 



