462 SCIENCE PROGRESS. 



tribution since Maillard (39), containing some of the cellular 

 cryptogams, is the first part (40) of the long promised 

 Flora. It contains the vascular cryptogams, and includes 

 197 species of ferns, of which twenty-three are regarded 

 as peculiar to the island. 



Since the publication of Baker's Flora of Mauritius 

 some of the outlying* islets have been more thoroughly 

 explored, with interesting results ; among them Round 

 Island. This is one of several small volcanic islands at 

 the north end of Mauritius. It is situated about thirteen 

 miles from the mainland, rising like a dome out of the 

 ocean to a height of a little more than a thousand feet, and 

 is a mile across in its greatest diameter. Surgeon- Major 

 Johnston states (41) that the greater part of the surface of 

 the island is composed of bare rocks of volcanic tuff, from 

 which almost all the soil has been washed away into the 

 sea by heavy rains. From a distance the island has a very 

 barren aspect, its steep, brown, rocky sides having only 

 small clusters and scattered individuals of palms and screw- 

 pines to break the general monotony of its appearance. 

 Palms and screw-pines are indeed so prominent as to 

 appear to constitute the whole of the arboreous vegetation, 

 though small trees exist of the genera Terminalia (Com- 

 bretaceae) and Diospyros (Ebenaceae). There are three 

 distinct palms, namely, Latania Loddigesii, Hyophorbe 

 amaricaulis and Dictyosperma album. All three are com- 

 mon in the island, and the second is not known to exist 

 elsewhere in a wild state. The only screw-pine (Pandamts 

 Vandermeerschii) is also common on this and some of the 

 adjacent islets, but it has not been found on the mainland. 

 Major Johnston also observed several plants of P. utilis ; 

 but the conditions under which they were found suggested 

 the probability of their having sprung from seeds sown by 

 one of the early visitors. Loniatophyllum borbonicum 

 (Liliaceae) is another noteworthy native plant. It is of 

 tree-like habit, resembling an Aloe, and inhabits Mauritius, 

 Bourbon and Aldabra. 



Altogether about forty species of vascular plants are 

 recorded from Round Island. Except the almost certainly 



