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[Vol. 9 



GARDEN 



oblanceolate type of petal has been developed four times within 

 the genus, since it is found in C. suljureus, C. Cooperi, C. anceps, 

 and C. lasiophyllus. With the exception of the last two, these 

 species are not closely related. The primitive color may have 

 been purple. 



Inflorescence.— The flower cluster in species of Caulanthus is, 

 almost without exception, a lax raceme. The most interesting 

 and significant detail of the inflorescence is to be found in the 

 mature pedicels. In C. Cooperi, C. simulant, C. heterophyllus, 

 and C. stenocarpus the pedicels are recurved and the pods de- 

 flexed. In C. Coulteri, C. californicus, C. anceps, and C. lasio- 

 phyllus the pedicels are either recurved or curved upwards and 

 the pods in consequence are either deflexed or erect. With these 

 species must be associated C. Lemmonii and C. flavescens. So far 

 as is known the pods of these are always erect. This group of ten 

 species is evidently closely related, to judge from other points 

 of similarity, and is partially characterized by a tendency to de- 

 velop recurved pedicels and deflexed pods. This character pre- 

 sents a strong argument for the retention of these ten species 

 within one genus. 



Leaves.— In ten species the cauline leaves are conspicuously 

 amplexicaul by auriculate basal lobes. In eight they are either 

 sessile or, usually, distinctly petioled; in neither case are the 

 basal lobes developed. Three or four species have leaves that 

 are nearly or quite entire. The leaves of the other fourteen or 

 fifteen species are, in part at least, definitely toothed. In Caulan- 

 thus no such definite differentiation between radical and cauline 

 leaves occurs as in Thelypodium but in most species the leaves 

 near the base of the stem are usually longer, narrower, and more 

 distinctly toothed than the upper stem-leaves. Since these basal 

 leaves are often more closely crowded upon the stem than are 

 the upper ones, there is an approximation to the rosette habit. 

 The inter-specific leaf variation seems to offer the best guide 

 to the phylogenetic development within the genus. To judge 

 from findings in Thelypodium the amplexicaul leaf would be 

 considered primitive. Since this is the more usual form it is 

 easier to examine those species with petioled than with clasping 

 leaves. These are C. glaucus, C. pilosus, C. Hallii, C. major, C. 

 crassicaulis, C. flavescens, C. anceps, and C. lasiophyllus. Five 

 of these are species in which trichomes are developed. Two of 

 the glabrous species, C. major and C. crassicaulis, are peren- 

 nials. The first five species, and this includes the third glabrous 



