318 Floristik, Geographie, Systematik etc. 



Hemsley in the Report on the Botany of the Atlantic Islands 

 enumerated it as a doubtful E. Chamaesyce probably a new species. 

 Roxburgh treated it as an introduced plant and named it, erron- 

 eously, E. rosea, while Bure hell regarded it as E. prostrata. Thel- 

 lung has now had an opportunity of examining some fragments 

 of the St. Helena plant, and Stapf has examined the fairly ample 

 material preserved in the Kew coUections, the result being that 

 they have come to the conclusion that the plant represents a new 

 species as suggested by Hemsley. They have therefore described 

 it as Euphorbia (§ AnisophyUiun) heletiiana, Thellung et Stapf. 



E. M. Cotton. . 



Wernham, H. F., Pseudomussaenda: a new genus oi Rubiaceae. 

 (Journ. Bot. LIV. 646. p. 297—303. Oct. 1916.) 



The Rubiaceous genus Mtissaenda gives its name to the tribe 

 Mussaendeae, characterized by valvate aestivation of the corolla- 

 lobes, and fleshy, indehiscent fruit containing many small angular 

 seeds. One species, M. luteola was described by Delile in 1826. 

 The same species had been previously described under the genera 

 Ophiorhisa and Manettia: O. lanceolata, by Forskai and M. lance- 

 olata Vahl. The author considers that the character of the fruit 

 suffices not only to remove it from the genus Mussaenda , but also 

 from the tribe Mussaendeae. The new genus Pseudomussaenda is 

 therefore proposed and this includes two other species with capsular 

 fruits previously described under Mussaenda and a new species 

 recently coUected by Gossweiler. The synonymy is therefore 

 as foUows: 



1. P. lanceolata, comb. nov. {Mussaenda luteola, Del.). 



2. P. Monteiroi, nom. nov. {Mussaenda Monteiroij Wernham). 



3. P. G ossit) eiler i, sp. nov. (Angola). 



4. P. capsidifera , comb. nov. {Mussaenda capsiilifera , Balf. fil.). 

 A few new species of Mussaenda, coUected in Tropica! Africa 



are also described, viz.: M. entomophila , M. macrosiphon, M. Debe- 

 auxii, M. Gossweileri. E. M. Cotton. 



Willis, J. C, The distribution of species in New Zealand. 

 (Ann. Bot. XXX. N". CXIX. p. 437—457. Juli 1916.) 



The fiora of New Zealand is studied in this paper from the 

 point of view of my hypothesis, that the geographica! distribution 

 of a species (i. c. the area which it includes within its outer locali- 

 ties) within a fairly uniform country not broken by serious barriers 

 depends upon the age of that species within that country (the spe- 

 cies being taken in groups of twenty or so); and it affords striking 

 confirmation of that hypothesis. 



Starting from the hypothesis, numerous predictions were made 

 as to the phenomena which should be expected to be shown by 

 the fiora of New Zealand. and as all these predictions were 

 borne out by the facts, several new discoveries were thus made as 

 to the geographica! distribution of plants in those Islands. 



For example, it was predicted that if New Zealand were 

 divided into zones of 100 miles in width, the number of endemic 

 species would be comparatively small in the outer zones and would 

 mcrease steadily towards some central point (or points). This pro- 

 ved to be the case, not only with the whole flora but with all the 

 Single families and genera. It was further predicted and verified 



