ONAGRAKIE.E 555 



of the latter as exhibited in the primary leaves with the margin 

 similarly entire or toothed, and smooth or hairy. Most often 

 also there is a distinct constriction between the true cotyle- 

 donary portion and the foliar one ; and the former retains the 

 apical notch or emargination it may have possessed while still 

 in the seed. 



One of the simplest forms coming under observation and 

 showing a marginal constriction where intercalary growth 

 commences, is that of Lopezia coronata with ovate cotyledons, 

 the basal and foliar portion of which widens so as to produce 

 a tooth on each side. Fuchsia corymbifolia is somewhat 

 similar, but the cotyledons are emarginate. A very different 

 form is met with in Clarkia pulchella (fig. 361) which has 

 ovate, minutely emarginate, but otherwise entire cotyledons. 

 The foliar portion is indicated only by being minutely ciliate 

 at the margin like the first true leaves, and by the petiole ; 

 the cotyledons proper in the early stages being sessile, as in 

 all the types mentioned below. The cotyledons of Clarkia 

 sp. (figs. 357, 358) after germination are sessile, suborbicular, 

 emarginate, and vary to obcordate with a tooth in the notch, 

 gradually becoming petiolate and then oblong, constricted 

 in the middle, then panduriform, and ultimately rhomboid- 

 ovate and serrate below the constriction. The upper 

 portion retains its original form almost to the last, and con- 

 stitutes but a very small portion of the cotyledon when fully 

 developed. By unequal growth of the two sides of the stem 

 the cotyledons in many individual seedlings become alternate. 

 A similar development obtains amongst many of the species 

 of (Enothera and other genera. C. integripetala (fig. 362) 

 differs chiefly in the upper surface of the cotyledons being 

 minutely and papillosely pubescent all over, and in the two 

 portions being separated by a transverse brown line. The 

 pubescence is present in C. rhomboidea (fig. 360), but the 

 minute, marginal cilia are carried entirely round the cotyle- 

 dons which are oblong-ovate and entire in the foliar portion, 

 thus corresponding to the primary leaves as in all other cases 

 where intercalary growth prevails. The cotyledons of Eucha- 

 ridium concinnum differ from those of the last named in being 

 broadly ovate, obsoletely crenate below the constriction, and 



