CHARACE^— DR NORSTEDT AND ARTHUR BENNETT, F.L.S. 337 



CHARACEiE. 



By Dr 0. NOEDSTEDT and ARTHUR BENNETT, F.L.S. 



CHARA. 



Cham, Linn. Gen. n. 801. 



A genus almost universally distributed. 



0. SOCOtrensis, Nordst. in Ber. Deutsch. Bot. Ges. i. (1883), 241. 



C. haplostephana (ad C. diplostephanas accedens) bistipulata ecorticata monoica. 



Folia verticelli 10-11, ad genicula constricta, articulis circ. 5, elongatis 4, ultimo brevi, 

 mucroniformi, infimis tantum (interdum binis, saepe singulis) foliola et fructificationem 

 gerentibus. Foliola unilateralia, quaterna, acicularia, anteriora paullo longiora quam 

 lateralia sporangium non superantia, saepe multo breviora. Stipulse parvae, ovatae acum- 

 inata?, foliis adpressae, interdum tantum in unam seriem ordinatae, sed saepe in binas aculeis 

 in serie inferiore minoribus et quoque vulgo sursum directis. Sporangium 11-12-gyratum 

 (c. 0'85 mm. longum) coronula brevi obtusa (c. 0"2 mm. lata et OT mm. alta), nucleo atro 

 10-gyrato (c. 0'52 mm. longo et 0*32 mm. lato). 



Soeotra. B.C.S. nn. 747, 749, 750 pro parte. Near Tamarida, Schweinf. 

 n. 436 ; and near Katheng, Schweinf. n. 690. 

 Distrib. Endemic. 



A species varying somewhat in the amount of incrustation, and the relative 

 size of its parts. 



Nordstedt (loc. cit.) says of it — " The systematic position of this species is 

 somewhat doubtful." Of the species without a cortex there have been hitherto 

 known only five, and these all haplostephanous unistipulate. Of them C. 

 australis,T&. Br., and C. Wallichii, A. Br., are dioecious; C. corallina, Klein, and 

 C. succincta, A. Br., are monoecious, with fructification at the base of the whorls ; 

 and C. coronata (Ziz.) A. Br., is monoecious, with leaflets on the sterile segments. 

 In C. socotrensis, the upper sterile part of the leaf consists usually of only 

 primary segment cells without leaflets. The stipular cycle varies. Often one 

 finds two stipules for each leaf, under which may be seen a small slightly 

 projecting cell as is the case in other species, e.g., in C. coronata. But very 

 frequently this cell develops into a short usually upwardly directed bristle 

 or rounded knob, whereby the stipular cycle is doubled. One may therefore 



TRANS. ROY. SOC. EDIN. VOL. XXXI. 2 U 



