COMPOSITE 107 



and broader than the cotyledons. The first three or four 

 pairs of the leaves of Burrielia gracilis are precisely similar 

 to, but larger than, the cotyledons. The same may be said 

 of Bseria chrysostoma. The leaves of Microseris Bigelovii 

 are alternate, and the first six at least are linear and 

 slightly widened above the middle. The primary leaves of 

 Tragopogon crocifolium are also linear and slender and the 

 ultimate ones are never very wide. The cotyledons vary from 

 7'5-8'5 cm. in length. The two species last mentioned be- 

 long to the tribe Cichoriacese and therefore have no affinity 

 with those previously mentioned with linear cotyledons and 

 leaves. Tussilago Farfara (fig. 474) has linear cotyledons, 

 but they are small, and possibly do not exceed 5 or 6 mm. 

 in length. The first leaf is spathulate ; the second ovate ; 

 the third similar or triangular ; and the fourth and fifth 

 are cordate, recalling the primary ones of Senecio cruentus, 

 to which it is more closely allied than to any other in the 

 group of species with linear cotyledons. The narrowness 

 of the cotyledons as far as I have observed bears a direct 

 relation to that of the fruit and seed in which they were 

 developed. Lasthenia glabrata has linear cotyledons, and 

 the two first pairs of leaves are similar but larger. The 

 cotyledons of L. obtusifolia Bridgesii show a tendency to 

 be spathulate-linear, and while yet in the seed are spathu- 

 late-obovate. The species may be regarded as an inter- 

 mediate type tending towards those having strictly spathulate 

 cotyledons. 



A fairly representative type of the spathulate cotyledons 

 is furnished by Cryptostemma calendulaceum. The first two 

 leaves are spathulate and slightly dentate. Succeeding ones 

 are broader, and from the fourth onward they are lyrate- 

 pinnatifid. Evolution of the leaves is also exhibited by Dahlia 

 variabilis, the first four pairs of which are ovate, and the fifth 

 pair more or less pinnatisect. Tagetes patula (fig. 467) and 

 T. glandulifera have also very typical cotyledons, with the 

 primary leaves opposite, pinnatisect, and their segments 

 extremely unequal in size. A peculiarity of T. patula is that 

 the under side of the cotyledon has a submarginal line of 

 glands similar to those on the leaves. The first pair of leaves 



