78 BRODIyEA GRANDIFLORA. CALIFORNIA HYACINTH. 



and some of its allies three of the six leaves which should have 

 been transformed into stamens have been but imperfectly devel- 

 oped, and are left in a subpetaloid condition. These sterile or 

 petaloid stamens are well shown in the flower marked Fig. 5 on 

 our plate, and can also be noticed in the flower in a horizontal 

 position to the left of Fig. 5. 



The student will find it well worth while to compare the 

 flowers of the eenus Bvodiaa with those of other allied orders, 

 as such a comparison will clearly show that the differences, 

 seemingly so great, between the various families of plants, are 

 often due simply to greater or less arrest or acceleration of the 

 growth-waves which form the verticils. Endogenous plants, to 

 which great division the Liliaccce belong, have their growth- 

 cycles in threes; but the two verticils, which in other plants 

 form the calyx and the corolla, are arrested in such quick suc- 

 cession in the Liliaccce that they are both almost equally devel- 

 oped. It is, therefore, scarcely possible to distinguish between 

 them, and hence both are looked upon as one structure, so that, 

 in the case of a Lily, we do not speak of three sepals and three 

 petals, but simjoly of a six-parted perianth or flower-cup. But if 

 we examine an Alisma, or a Tradcscantia, as types of two natural 

 orders closely allied to the Liliacccr, we shall find that each ver- 

 ticil has been acted on by a separate growth-wave, and that the 

 differentiation of the two verticils has been sufficiently great to 

 produce a perianth in which the calycine and the petaloid divis- 

 ions can be readily noticed. Returning to the Liliacca, and 

 proceeding to study the development of the verticils following 

 those which produced the perianth, we shall again perceive that 

 two sets of leaves of three each have been caught quite or nearly 

 by the same growth-wave, and have been converted into six 

 stamens. In most of the genera of the order these stamens 

 are almost alike ; but in Brodicea the lower, or first of the two 

 staminate verticils has evidently been caught by the wave which 

 formed the perianth, and thus it has assumed the form of the 

 sterile petaloid processes which we have before alluded to (see 



