252 The Gen7is Colletia. [Sess. 



Y.—TEE GENUS COLLETIA. 

 By Mr HUGH FRASER. 



{Read Feb. S7, 1SS9.) 



This genus — named in honour of M. Collet, a celebrated French 

 botanist — forms a part of the Natural Order of the Ehaninacese, 

 which consists of about 40 genera and 260 species of small 

 trees and shrubs, distributed over the greater part of the globe, 

 and varying very much in habit of growth and general appear- 

 ance. Many of them contribute to the convenience and neces- 

 sities of man by their woods, barks, and fruits. The order is 

 represented in this country by two species — the one Ehamnus 

 frangula, which supplies the charcoal so much used in the 

 manufacture of the finest gunpowder ; the other E. catharticus, 

 which is used in medicine. Chili and Peru are the homes of 

 the Colletias, though the Discarias of Australia and New 

 Zealand, according to some authorities, should be merged in 

 the genus, as they have certainly close affinities with these, 

 both botanically and in general characteristics. In this country 

 Colletias can only be regarded as half-hardy, and consist of 

 small trees and dwarf shrubs, varying in height from about 

 two feet to twelve feet. In some districts, however, they 

 withstand the rigours of our winter, and grow fairly well in 

 sheltered sitiiations, and especially when enjoying the shelter 

 of a wall with a warm aspect. In our own Botanic Garden 

 several of the forms grow wonderfully well ; and on a recent 

 visit to the beautiful and highly interesting garden of Charles 

 Jenner, Esq., Easter Duddingstone, I found two specimens, 

 the one being C. spinosa and the other C. cruciata, in robust 

 health, from eight to ten feet high. In Dublin, however, and 

 notably at Trinity College Botanic Gardens, I noticed several 

 plants which seemed to be quite at home. 



Among the peculiarities of this very interesting group of 

 plants may be noted the small development of leaves. They 

 do produce leaves on their young growth, but soon shed them, 

 so that for practical leaf-functions their real leaves are useless. 

 Another curious feature of the Colletias is their spines, with 

 which all are armed with a profusion rarely seen in other 



