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Gucurbitaceous plants are everywhere grown around and before the houses on bamboo 

 trailings or other supports, offering a friendly sight during the hottest part of the year, when, 

 with the exception of tamarind and mangos, all trees have shed their leaves. 



c. Wade places, ruins, etc. The vegetation that grows on waste places, along road- 

 sides and in rubbishy places, such as are called by botanists ruderata, as also the plants that 

 grow on old brick walls, or on ruined pagodas, are often very interesting, although the 

 greater part of these plants are usually weeds of general disribution. 



It is not necessary here to go more fully into this matter. I therefore content myself 

 with summing up a few of the names of the more frequent plants that grow : 



(1.) On waste places and along road-sides. 



(2.) On rubbishy places and old brick work. 



On the former are seen chiefly Leonotis nepetaefolia, locally Jatropha glandulifera, Ocy- 

 mum, Ricinus communis, Tephrosia pui-purea, several species of Blumea, such as B. Wightiana, 

 lacera^ etc., Phaylopsis, Triumfetta angulata, Spilanthes acmella and paniculata, Vernonia 

 cinerea, Cynmopsis puhescens, Chrysopocjon aciculatus, Eleusine Indica, Zoysia pungens, Sidae, 

 Sporobolus, and numerous others of similar stamp. 



In localities of the latter nature, and more especially on old ruined pagodas, we find a 

 number of curious plants, which we were accustomed to collect chiefly on diluvial and 

 other rocky formations, and such plants attract our attention here* still more, as they are 

 found growing on these pagodas in the midst of alluvium, where, for 30 to 40 miles around, 

 no vestige can be seen of them, except on old brick-work in villages, a situation identical 

 with the above, only differing sometimes in the amount of shade and moisture. But even 

 this is of no consequence, for if we walk round a circular or quadrangular pagoda, we find 

 fully developed all the changes that exposure creates. 



Burnt clay (brick -stones) possesses (like iron-oxyde) to a remarkable degree the capacity 

 of forming (with ammonia) solid combinations. It absorbs with avidity ammonia from the 

 atmosphere and retains it, and Liebig therefore calls burnt clay and soils rich in iron-oxyde 

 (like laterite) veritable absorbers of ammonia. It is no doubt due to this quality that old 

 ruins etc. possess such a prolific vegetation. 



The following are the plants I met with more generally in such localities : Blumea 

 runcinata and Jlava, Knoxia lasiocarpa, Triumfetta angulata, Sida acuta and rhomhifolia, Ver- 

 nonia cinerea, Lindenbergia urticaefolia and macrostachya, Scoparia dulcis, Achyranthes aspera, 

 Boerhaavia repanda ; Phyllanthiis niruri and urinaria, Euphorbia pilulifera, Spermacoce, Bat- 

 rathemm latifolium, Apocopis, Sonerila tenera, Selaginella tenera and Junghuhnii, Pogonatherum 

 crinitum, Cheilanthes argentea, Adiantum lunulatum, and caudatum, Osbeckia chinensis ? , CrotU' 

 laria acicularis, Amarantus sanguineus, Celosia cristuta (the purple variety chiefly), Schizachyrium 

 brevifolium, Ero/jrostis amabilis, Brownei, etc., Vandellia Crustacea, Canscora diffusa, Sida cor- 

 difolia, Ageratum eonyzoides, sometimes Gomphrena globosa, Ipomoea viti/olia and other species, 

 Lepidagaihis fasciculata and recurva, Nelsonia origanifolia, Emilia sonchifolia, Leucas, Rungia 

 peciinata, etc. etc. Some Algae, like Scytonema cinereum, along with acrocarpous mosses 

 (chiefly Pottia and Tortula) are also frequently seen along the shady sides. 



As in other waste places, so also here, coarse grasses like Saccharum spontaneum, Polytoca 

 heteroclita, Thyssanolaena acarifera spring up especially along the sunny sides, while trees 

 also (chiefly fig-trees) soon settle themselves on the ruins and grow up undisturbed. 



3. Naturalized plants. 



The naturalized plants are of some interest, as their spread and acclimatisation often 

 give some hints with regard to the migration of plants generally. Some suppose also that 

 plants from the new world, when brought over, supersede those of the old world. I myself 

 never could understand clearly this hypothesis, and believe it has originated with men, who 

 see only the effects, but not the cause of such supersession. 



Light seems to be the principal regulator of colonisation of introduced plants. Light- 

 loving plants have everywhere the best chance of succeeding in the struggle with indigenous 

 plants. Cultivation, therefore, greatly favours the spread, while forests, and partially also 

 savannahs, set a powerful check to their dissemination. Again shade-lovers, even in favour- 

 able countries, like Java, spread very slowly, and even when completely established (like a 

 few Brazilian plants about Buitenzorg etc. in W. Java) they remain localized. This is 

 just what really takes place with the same class of indigenous plants, and any one who has 

 botanized in tropical forests must have observed the patchy occurrence of shade-loving 

 herbs. The scanty dissemination of exotic trees in India (if we except Anona squamosa and a 



* It formed at one time a matter of no little perplexity to me to find such plants, as Clematis Gouriana, 

 Parana etc., growing at Gour (an ancient town, E. of Rajraehal, Bengal), in the midst of alluvium. I set out for 

 this place to enquire into this anomalous occurrence, and found to my full satisfaction all those plauts growing ou 

 the debria of the colossal ruins (aa artiUcial diluvial fonuatioQ indeed !), but nowhere in alluvium. 



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