Foweraker. — Mat-plants and Cushion-plants of C'a«.? River Bed. 15 



(b.) Leaf. — The leaves are obovate-spathulate or linear-spathulate, about 

 2 mm. long and 1-25 mm. broad. The lamina is broadly spathulate, folded 

 inwards in a conduplicate manner, thick, densely woolly on both surfaces, 

 especially the inner, and most so at the junction of sheath and lamina. 

 Apex truncate, obscurely emarginate, with a minute papilla at the ex- 

 tremity. The sheath is not broader than the lamina. During the winter 

 the leaf-margins have a brownish tinge, due to anthocyan, which gives 

 a faint pinkish-brown tinge to the whole mat. 



The rosettes are small (about 2 mm. across), and on an average four 

 leaves are visible from above. There is no compactness of growth, so the 

 rosettes do not enter as a factor into forming a surface. A transverse 

 section of the rosette shows the large space occupied in the terminal bud 

 bv the tomentum (fig. 4), which almost equals the leaf in thickness. This 



tornentum 



C. E. F. del. 



Fig. 4. — Raoulia australis. Diagram of transverse section 

 of rosette : shaded portion represents tomentum. 



layer of tomentum plays an important role in protection during frosts. 

 It should function as the tomentum in the large rosettes of Celmisia 

 spectabilis, dealt with later. 



The leaf-anatomy differs from that of the leaf of R. tenuicaulis only 

 in the slightly thicker cuticle, greater density of hairs, and chlorenchyma 

 more closely packed. 



(c.) Root.- — This species forms its mat somewhat more slowly than does 

 R. tenuicaulis. The primary tap-root remains in evidence longer, and 

 the prostrate branches are slower in putting forth adventitious roots. As 

 no filling-material exists, no roots can be given off from the branchlets 

 into the central mass. 



The root-anatomy is as in R. tenuicaulis, except for a more general 

 lignification of the tissues. 



(d.) Flower and Fruit. — The flower-heads are cylindrical, 0-5 mm. to 

 0-75 mm. long, with involucral bracts in about three series. The florets 

 are ten to twenty, about half of which are female florets on the exterior. 

 The cypsela is oblong, minutely pubescent, and crowned with a dense 

 pappus tuft. 



(y.) Epharmonic Variations. 



In its natural habitat this plant varies mainly in the size of the leaves 

 and their degree of hairiness. Plants grown in a greenhouse at sea-level 

 for six months developed elongated branchlets, with larger, flatter, less 



