1835.] Transactions of the Linnean Society of London. 387 



is divided by the author into three tribes, 1. Aegicereae, with an 

 erect embryo ; 2. Ardisiae, including the bulk of true Myrsineae ; 

 3. Moeseae, with an inferior ovarium, approaching to primulaceae. 



He has proposed two new genera, Weigeltia and Conomorpha, 

 and a third, Choripetalum, which has not been sufficiently examined. 

 The species of this order produce a resinous substance, which appears 

 in the form of dots or reservoirs, in different parts of the plant, 

 chiefly on the leaves, flowers, and berries, and also in the hard wood 

 of the Myrsine and Aegiceras. It melts and burns in the flame of a 

 candle, is not soluble in water, but is so in oil or alcohol when mode- 

 rately heated, giving to the latter a rose colour, These facts were 

 particularly observed in the berries of the M. semiserrata. The 

 dots are dark or light brown, reddish or yellow, varying in size, 

 shape and position, in different species. The fruit of Embelia 

 ribes possesses a styptic taste, which the author supposes to depend 

 on this resinous substance. 



Of 180 species of myrsineae 58 are described for the first time 

 by the author. They grow commonly on the hilly and mountainous 

 regions of the hottest parts of the globe. None have yet been found 

 beyond the 39th or 40th degree of latitude, viz. in Japan, whilst 

 they abound in Java and in some parts of India and South America. 

 No species is known in Africa except at the Cape and at the Canary 

 Islands, Mauritius, Bourbon and Madagascar. The 180 species are 

 distributed as follows : 112 in Asia and New Holland, 48 in America, 

 and 20 in Africa. 



Mr Don, in his paper, shews that the form of aestivation of the 

 corolla is of great importance as a character to distinguish different 

 families, especially among the monopetalous orders, except in the 

 order Rubiaceae, where examples of every kind of modification 

 occur. In the Cinchona grandi flora and rosea it is imbricate, in 

 C lanceolata and the rest of the true cinchonae it is valvate, while 

 in the West Indian species it is induplicate and in the C exelsa 

 plaited. Of the genus cinchona he enumerates seventeen true species. 

 2. Combuena, (C grandiflora) two species ; obtusifolia and acumi- 

 nati ; 3. Lasionema ( C rosea) roseum ; 4. Exostema, seven species ; 

 5. Hymenodictyon (C excelsa) exelsum and thyrsiflorum ; 6. Lu- 

 culia gratissima and cuneifolia ; % Pinckneya pubens. 



The other paper of Mr. Don is upon the Tropaeolum penta- 

 phyllum of Lamarck, which has been introduced into this country 

 by Mr. Neill of Edinburgh. He shews that it differs from the genus 

 Tropaeolum in having the aestivation of its calyx valvate, that of 

 Tropaeolum being imbricate. In the nature of its fruit, which is a 

 black juicy berry resembling the Zante grape, and in the reduced 

 number of its petals. He has formed it into a new genus, and 

 terms it Chymocarpus pentaphyllus. Its calyx is persistent, while 

 that of Tropaeolum is deciduous. The embryo is small and white, 

 contained in a thin cartilaginous testa, and the cotyledons round and 

 compressed. It belongs to the natural order Tropaeoleae, and is a 

 native of the sandy plains of Buenos Ayres. It was first observed by 

 Commerson, and afterwards by Tweedie. 



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