OF THE LEAVES OF CERTAIN SPECIES OF VERONICA. 265 
Heterophylly of the Species of Group Е, 
These highly modified forms of Veronica are all heterophyllous *. If they 
are grown under conditions of greatly inereased moisture and diminished 
illumination they produce spreading leaves ї. In the seedling stage also, so 
far as is known, the leaves are spreading ў $ ; so that adult forms producing 
such leaves may be regarded as reversions to a primitive condition. Material 
of V. cupressoides and V. Armstrongii was obtained in this state from plants 
grown in a shady and moist house in the Edinburgh Botanic Gardens. 
Г cupressoides, Hook. f. ||. 
The leaves are small and petiolate and somewhat pinnatifid, owing to the 
projection of lateral veins. The epidermis is less thickened than in the type. 
Fic. 15. 
Transverse section of “ reversion " leaf of V. cupressoides. x 200. 
Stomata occur оп both sides. The mesophyll is very like that of V. Gode- 
froyana (belonging to Group D), but more homogeneous (fig. 15). The 
xylem of the bundles is quite normal. 
V. Armstrong. 
The leaves have short petiolesand toothed laminæ. Stomata occur on both 
sides, but are more numerous above. The mesophyll is very homogeneous. 
* Lindsay (1889). t Goebel (1908), 
t Goebel (1900). $ Cockayne (1900). 
|| Goebel, Pfl. Schild. p. 19 (1889). 
