PHANEROGAMS — PROFESSOR BAYLEY BALFOUR. 87 



D. dehiscens, Balf. fil. in Proc. Eoy. Soc. Edin. xi. (1882), 511. Tab. XXII. 



Fruticosus ; ramulis foliisque juvenilibus pubescenti-hirtis; pinnis 2-5-jugis glandulis stipi- 



tatis, foliolis 8-15-jugis oblongis obliquis ; spicis cylindraceis ; legumine debiscente. 

 Frutex glabrescens ramis teretibus ramulisque juvenilibus angulosis pubescenti-hirtis axillari- 

 bus saepe spinosis. Folia ungue molli terminata pinnis 2-5-jugis rhaebi cum glandulo 

 umbilicato stipitato inter jugas instructa; foliola sessilia 8-15-juga obliqua oblonga sub- 

 mucronulata \ poll, longa. Flores in spicas densas solitares axillares pedunculatas 1£ 

 poll, longas congesti. Bractece scapboideae minutse ciliatae calyci subaequilongae. Calyx 

 minute dentatus ^ poll, longus breviter ciliatus. Corolla ^ poll, longa deltoideo-lobata, 

 petalis per partem superiorem quartam liberis ; glandulae staminibus breviores. Stamin- 

 odia contorta. Ovarium breviter stipitatum villosum. Lcgumen planum rectum v. vix 

 tortuosum oblanceolatum, 1£ poll, longum £ poll, latum 4-5 ad apicem pedunculi conferti , 

 valvis extus pubescentibus sublignosis maturibus recur vis Semina £ poll. diam. exalbum- 

 inosa. 



Socotra. On Kadhab and Hadibu plains. B.C.S. n. 365. Schweinf. n. 689. 

 Distrib. Endemic. 



The facies of this plant is decidedly Dichrostacyoid, yet it is not without 

 violence to the generic character that it is included in the genus. Like all the 

 genera of the Mimosean tribe Adenantherece, this genus has exalbuminous 

 seeds. It has also a dehiscent thick legume. Now in both these characters our 

 plant differs from the generic type, and resembles the genera of the tribe Pipta- 

 deniece, and in that tribe its nearest ally is Piptadenia itself. But as the whole 

 habit, the presence of neuter flowers at the base of the spikes, and the stipitate 

 glands between the pairs of pinnae on the leaves are so characteristic of 

 Dichrostachys, and as Piptadenia is essentially an American genus, having only 

 three specific representatives in the old world, we have placed our plant in the 

 genus Dichrostachys. 



26. ACACIA. 



Acacia, Willd. Spec. PI. iv. 1049 ; Benth. et Hook. Gen. PI. i. 594. 



A vast genus of warmer regions, especially abundant in Australia and 

 Africa. There are three species in Socotra, and of them two are endemic, and 

 the third, as yet imperfectly known, is probably also endemic. 



1. A. socotrana, Balf. fil. in Proc. Roy. Soc. Edin. xi. (1882), 511. 

 Tab. XXXIII. 



Suffruticosa glabrescens ; spinis primum tomentosis rectisque, demum glabris apiceque lente 

 recurvis foliis aequilongis ; pinnis 7-8-jugis, foliolis 10-20-jugis parvis oblongis obtusis ; 

 involucello pedunculi persistente ; legumine stipitato foliis duplolongiore marginibus planis 

 valvisque velutinis nervosis lignosis. 



Suffrutex spinosus cortice papyraceo glabrescens. Rami subprostrati, ramuli juveniles pubes- 

 centes v. subtomentosi. Spina} stipulares f— 2 poll, longi primum tomentosae rectae demum 

 glabrae albidae apiceque lente recurvatae subfusco-nigrae. Folia bipinnata apice subspinosa 

 rhachi pubescente prope basim glandula unica concava substipitata pilis radiatis cincta 

 instructa; pinnae 7-8-jugae subspinosae; foliola 10-20-juga oblonga obtusa subtus pallidiora 



