March, 1896. DISPERSAL OF SEEDS BY BIRDS. 187 



very soon make their way in. Now, the Malay Peninsula is almost 

 entirely covered with jungle of the densest character, and the result 

 is that Compositae are almost entirely absent from the native flora. 

 Along the open edges of the sea-coast, however, we have Wedelia, the 

 fruits of which, unprovided with a pappus, are drifted along the 

 coast in the sea : Pluchea indica, the fruits of which have a pappus, 

 and are wind-dispersed ; this latter, though usually a sea-shore plant, 

 has been found by me on cleared ground in the interior of Singapore : 

 Gynuva savmentosa, a climber to the tops of trees in the jungles, 

 from which altitude its fruits can drift like those of other jungle- 

 climbers : and Vemonia arborea, a lofty tree, which, however, occurs 

 only on the outside of the jungles or in the open country. The 

 remaining twenty-five or thirty species are apparently introduced 

 weeds, and wander but a short distance from cultivated ground. 



In some orders of plants the modifications for dispersal of seed 

 are on the same lines in all the species, but in almost every order 

 there are exceptional modifications. Thus the Orchideae, whether 

 epiphytic or terrestrial, have capsules filled with fine seed, the testa 

 being prolonged into a thin process, by the aid of which the seeds are 

 drifted to suitable spots by the wind. Vanilla, however, is an 

 exception. It has a sweet, succulent, fleshy pod containing minute 

 seed, unprovided with any prolongation. It is eaten by animals, and 

 the seed is thus dispersed. 



Most of the Apocynaceae have plumed seeds, which are dissemi- 

 nated by the wind ; they are here either climbers or large trees, more 

 rarely shrubs. Cevbera and Ochrosia, natives of the banks of tidal rivers, 

 have large drupes, which are adapted for sea-dispersal ; Kopsia has an 

 inconspicuous drupe with a single seed, and is apparently dispersed 

 by mammals ; Willughbeia and allied genera have large berries eaten 

 by mammals and birds ; Tabemamontana, often a low shrub, inhabit- 

 ing dense jungles, has a brilliant orange capsule, the seeds of which 

 are enclosed in a crimson aril and are devoured by birds. Sometimes, 

 however, very closely allied plants have entirely distinct means of 

 dissemination ; thus Neuwiedia Lindleyi, Rolfe (Apostasiaceae), and N. 

 Griffithii, Rchb. fil, have capsular fruits with seeds resembling those of 

 orchids, while N. Curtisii, Rolfe, a plant which so closely resembles 

 N. Lindleyi, Rolfe, both in habit and flower as sometimes to be hardly 

 distinguishable at the first glance, has orange-coloured fleshy berries, 

 with minute globose seeds, the testa of which is not developed into 

 wings as in that plant. 



Perhaps no group of plants shows so much variation in its means 

 of dispersal as the Cucurbitaceae. Thus Bryonia, a native of open 

 woods and hedges where frugivorous birds are common, has small 

 scarlet berries. Trichosanthes, on the other hand, a lofty climber in the 

 tangled masses of creepers which fringe the jungles of the East Indies, 

 has large scarlet fruit conspicuous from afar, but too large to be 

 swallowed whole. The birds, therefore, tear it to bits, and as the 



