234 the journal of botany 



Distribution of the African Species. 



As just now mentioned, about a dozen species are peculiar 

 to Madagascar and the neighbouring Mascarine Islands. One 

 species, M. arcuata, is common to these islands and to the African 

 Continent. M. frond osa, widely distributed over Malaya, India, 

 China, and Polynesia, has not been recorded from Africa. 



M. elegans and M. arcuata have the widest distribution of all 

 the African species. The former appears in Senegal, where it is 

 the sole representative of the genus ; following the west coast, we 

 find records of it in Sierra Leone, from Liberia to Nigeria, in the 

 Cameroons, the Congo basin, and Angola ; in Central Africa it 

 occurs in Monbuttu-land ; and it has been collected by Dawe in 

 Uganda, its most easterly station. Following a similar direction, 

 M. arcuata has been found from Sierra Leone to Angola ; in 

 Niamniam-land and Djur-land, in Uganda, and in Nyasa-land. 

 The same species occurs abundantly about the east coast from 

 Mombasa to Gaza-land, and its distribution extends to the 

 Mascarine Islands. 



M. erythrophylla, a striking species commonly cultivated, with 

 showy red flowers and petaloid calyx-lobes, is found along the 

 west coast from Sierra Leone to the Cameroons, in the Congo 

 basin and Angola, and, like M. elegans, as far east as Uganda. 

 Two other West African species are M. Isertiana and M. grandi- 

 flora, the distribution of the former extending from Sierra Leone 

 to the Cameroon Eiver. The latter, a very distinct species (q. v.), 

 has been recorded only from Sierra Leone and Liberia. M. tenui- 

 flora occurs from Nigeria to the Cameroons, and, as a variety, in 

 Angola. For the rest, one species is endemic in Sierra Leone, 

 three in Liberia, two in Lagos, one in the Gold Coast, one in 

 Nigeria, one in the Cameroons, one in Gaboon, one in the Congo 

 basin, three in Angola, four in Central Africa (Nile-land), and six 

 about the east coast. 



Key to the Species. 

 Note. — The term "calyx-lobes," unless otherwise stated, refers 

 throughout to the normal small lobes, not to those with petaloid 

 development. 



a. Calyx-lobes short and tooth-like, or subulate, then rarely so 

 much as 2*5 mm. long (M. monticola) ; or broadly lanceolate, 

 triangular, ovate or oblong, then usually less than 3 mm., 

 rarely so much as 7 mm. {M. Afzelii). 



Branchlets scabrid with rigid backwardly-curved hairs 



1. scabrida. 

 Branchlets not scabrid. 

 Corolla-tube densely yellow pubescent or hirsute ex- 

 ternally, with hairs all directed to base. 



Calyx-lobes obtuse 2. rivularis. 



Calyx-lobes apiculate-acuminate 3. Afzelii. 



Corolla-tube hairs, if present, not directed toward the 

 base, except occasionally in lower part, 

 b. Primary lateral leaf-veins 7 at least on either side 

 of the midrib, usually 10 or more. 



