INTRODUCTORY CHAPTER. xlix 



representative of Thymelseacese, differs conspicuously from the generic character 

 in the want of perianth-scales, a feature in which it resembles an undescribed 

 east African species collected by Hildebrandt. Orchidese has as its only species 

 the endemic Habenaria socotrana, with an affinity in H. attenuata, a plant of the 

 Cameroons. The single species of Aristolochiacese and of Loranthacese is in 

 each case probably endemic, but our specimens are not sufficient to admit of 

 determination. Acridocarpus orientalis, the only representative of Mal- 

 pighiacese, although not endemic, is worthy of note, because it is elsewhere 

 only known from the vicinity of Muscat. 



I must not omit to note here, at the conclusion of this brief survey of 

 orders, the remarkable plant Wettstedia socotrana. It is placed in the system 

 as an anomalous genus belonging to Bicarpellate Gamopetalse, but the order 

 in which it should find a position is difficult to fix. Mr Bentham would 

 place it in Verbenacese, but it has many resemblances with Boragineae. This 

 question is discussed under the description of the plant. 



The endemic flora consists of 206 species — 17 being annuals — which fall 

 into 136 genera, of which 20 are themselves endemic ; otherwise expressed 

 this is : — 365 per cent, or more than one-third of the total species, are endemic, 

 and 6 3 per cent, or just about one-fifteenth of the total genera, are endemic. 

 This is a large proportion of endemic species, much greater than that in 

 the Seychelles and Mascarene Islands, and about the same as in Madagascar, 

 but the proportion of endemic genera is much less than in the latter island. 

 In speaking of the orders, I have already referred to the more striking of the 

 endemic species, and now I give the following list of them, adding a few 

 remarks upon affinities or other noteworthy points :— 



List of endemic species in the phanerogamic flora of Socotra. 



MENISPERMACE.JE. 



Cocculus Balfourii, Schweinf., . 



CRUC1FER.E. 



Farsetia prostrata, Balf. fil. 

 Brassica rostrata, Balf. fil. , 

 * Lachnocapsa spathulata, Balf. fil. , . 



CAPPARIDEE. 



Cleome socotrana, Balf. fil. , 



Resedace^;. 

 Reseda viridis, Balf. fil. , . 



V10LARIE.E. 

 Alsodeia socotrana, Balf. fil. 



* Species of endemic genera are printed in italics. 

 TRANS. ROY. SOC. EDIN. VOL. XXXI. Q 



Remarks, Affinities, &c. 

 Remarkable for its cladodiferous shrubby habit. 



Annual. Allied to Brassica Tournefortii. Gouan. and B. fruticulosa, 

 Cyr., Mediterranean and Oriental species. Has also an endemic 

 hirsute variety. 



An endemic genus of doubtful affinity. 



/Annual. Allied to Cleome arabica, Linn., a north African and 

 I Arabian species. 



f Allied to Reseda Auchcri, Boiss., a plant of Mesopotamia, Persia, 

 1 and Scindh. 



