AN ENUMERATION OF THE BRUNIACE^. 



By R. a. DUMMEB. 



In 1817 Robert Brown defined the order Bruniaceae in which 

 he included the genera Brunia, Staavia, Linconia, Thamnea, 

 and Erasvia,'-' and indicated its affinities to the HamameHdeae, a 

 systematic position which it has retained up to the present day. 

 Nevertheless, in other floral characters and in their anatomical 

 peculiarities the species collectively claim their recognition as a 

 distinct group. f The polymorphism and the varied cases of 

 mimicry which prevail in the order form one of its most striking 

 and interesting features, while the distribution of the species does 

 not lack in interest. These, which are wholly South African,]: 

 number about seventy, and are scattered over twelve genera, two 

 of which are monotypic. 



The remarkable resemblance of Atcdouinia capitata to certain 

 EriccB of the § Callista, or of Baspalia Schlechterii to the small 

 white-flowering Erica margaritacea is paralleled by Staavia 

 globosa, the apparent likeness of which to several Phylicas makes 

 dissection an absolute necessity. Similarly, the Compositae are 

 mimicked by various Staavias, notably S. Doclii, S. Broicnii, and 

 S. glutinosa, the first-named simulating a shrubby Chrysanthemum 

 in many respects. The genus Lonchostoma has masked its affinity 

 by assuming the guise of certain South African Thymelseaceae, 

 while Thamnea thesioides bears a superficial similarity to various 

 Thesia. 



Their xerophily is well shown in their more or less dwarfed 

 shrubby habit, the vertical position of the twigs, their restricted 

 leaf surface and oftentimes its silicification, the disposition of the 

 cricoid, pinoid, or myrtoid corky-tipped leaves, the paucity of the 

 stomata, and their limitation often to that side of the leaf appressed 



* Till recently the status of Erasma was a matter of conjecture, but an 

 inspection of the specimens at the British Museum shows it to be congeneric 

 with Lonchostoma. 



t This is confirmed by a recent study of the ovule. Cf. Saxton in Trans. 

 Roy. Soc. S. Africa, ii. i. 27-30 (1910). 



I Brongniart mentions that Commerson gathered Berzelia lanuginosa in 

 Madagascar, but this is erroneous. 



Journal of Botany, August, 1912. [Supplement II.] b 



