E. R Saunders 167 



Hairs are also as a rule absent froQi the first two or three leaves. In 

 those formed next the hairs follow the same order of distribution as in 

 semi-incana, but there is no ultimate general overspreading of the upper 

 surface. Some hairs may arise, mostly on the midrib and lateral veins, 

 but the green appearance of this side stands in sharp contrast with 

 the grey look of the under surface. Pods and sepals are both hoary, 

 seeming slightly but not markedly less so than in semi-incana. 



(c) The quarter-hoary, a grade lower still in the scale, has been 

 already described ^ The stem is glabrous and the range of variation in 

 the leaves is again shortened, the period preceding hair development 

 being longer ahd the maximum level attained lower. The plant, indeed, 

 shows no hairs until the leaf rosette is well developed. A few then 

 appear on the leaf-base margin. In the succeeding leaves which are 

 now attaining the maximum size they begin to extend along the whole 

 length to the apex. Or sometimes the apex may show a terminal hair 

 over the hydathode before this stage has been reached. Both surfaces 

 appear green, the upper being generally quite glabrous, the lower with, 

 at most, a thin sprinkling of hairs, chiefly on the prominent veins. 

 Sepals and pods are less hoary than in the preceding grade, the diminu- 

 tion in the degree of hairiness being most marked in the sepals. 



II. Glabrous. (Text-figures 1—3, Pis. VII, figs. 1, 5, 6, VIII, 

 figs. 7—9.) 



1. Sub-glabrous Group. In this group we may include four grades, 

 all of which, though presenting a glabrous appearance, are not absolutely 

 destitute of hairs throughout. Localisation of the hairs, in different 

 regions of the plant in two of these grades as compared with the other 

 two makes impracticable the arrangement of all four forms in one linear 

 series. They fall more naturally into position if we regard the down- 

 ward trend as diverging here along two descending lines, and the four 

 grades as showing a first and then a further stage in hair reduction as 

 we pursue either direction. In the higher grade in the one case the 

 hairs are detected without great difficulty, but in the other three they 

 are so few as only to be found, as a rule, after tedious search. For this 

 reason, though necessarily classified under the sub-glabrous category, it 

 was found in practice more convenient when dealing with mixed families 

 to include the latter gi-ades in the totals for the wholly glabrous class 

 and to ea.lculate the expectation on this basis. The characteristic fea- 

 tures of each grade are as follows : 



^ Journal of Genetics, loc. cit. p. 152. 

 Journ. of Gren. x 11 



