1912-13.] BOTANICAL SOCIETY OF EDINBURGH 179 



is nearer that genus than any other, in my opinion. It 

 strongly resembles in habit the tufted Arenarias so prevalent 

 in the north-west corner of Sikkim. where the climate is 

 markedly Tibetan in character, and recalls also Androaact 

 Selago of the same region. It has not been recorded from 

 Sikkim. traversed yearly by the native collectors of the 

 Lloyd Botanic Garden, and I suspect its habitat is in the 

 region lying to the north of the Sikkim frontier at an 

 altitude of at least 14.000 feet. 



Ox the Leaves of some Species of Banksia. 

 By R. C. Davie. MJL, B.Sc. 



Von Mohl in 1816 (" Vermischte Schriften."* p. 248) l noted 

 in the leaves of some species of Banksia the restriction of the 

 stomata to cavities lined with and partly occluded by hairs. 



An examination of the leaves of the >pecies of Banksia 

 growing in the Royal Botanic Garden. Edinburgh, has 

 revealed several types of leaf and various arrangements of 

 the stomata. In every case the stomata are raised. Except 

 in Banksia serrata, Linn., a small outer chamber (" Vorhof ") 

 is present: in B. serrata, Linn., the outer chamber is very 

 prominent. The stomata occur on both surfaces of the 

 leaf in this species : in the other species they are confined 

 to the lower surface of the leaf. 



In B. serrata, Linn., B. littoralis, R. Br., and B. spinulosa. 

 Sin., there are no cavities containing the stomata. In 

 B. collina, R. Br., B. coccinea, R. Br., and B. grand Is. 

 Willd., the stomata occur in shallow depressions between 

 the projecting nerves of the leaf. In B. attenuata, R. Br.. 

 B. irUegrifolia, Linn., and B. marginata, R. Br., these 

 depressions are deeper, but still occur only between the 

 nerves. In B. M R. Br.. B. paludosa, R. Br., and 



B. que re ifolia, R. Br., there are deep depressions in which 

 occur subsidiary cavities In B. ericaefolia, Linn., there are 

 two deep furrows formed by the revolute leaf-margins. 



An examination of material grown under natural con- 

 ditions will be made when plants are obtained from 

 Australia. 



1 Cf. E. Brown, " Suppl. pr. Prod. Flor. Xov. Holl., :; p. 34. 



