58 THE PHENOMENON OF 



furnished by the roses, where the stem grows onward 

 through the middle of the flower, and the Digitalis 

 purpurea monstrosa,^ in which the terminal flower is 

 grown through in the same way. The female head or 

 cone of Cycas may be regarded as a flower normally 

 grown through, with a retrogression from the (certainly 

 very imperfect) carpel-formation to the cataphyllary and 

 euphyllary formations. In Cycas, before the age of 

 blossoming, girdles of scale-hke cataphyllary leaves alter- 

 nate in regular order with girdles of pinnate euphyllary 

 leaves, which latter at all times form the crown of the 

 tree. This alternation has, in our botanical gardens at 

 least, a biennial period, so that the crown of euphyllary 

 leaves undergoes Rejuvenescence every two years. When 

 the fruit-bearing age arrives, this alternation becomes 

 more complicated, the order being as follows : 1, a zone 

 of cataphyllary leaves (forming before the unfolding of 

 the succeeding parts a large, shortly conical, terminal 

 bud) ; 2, a zone of euphyllary leaves ; 3, another zone of 

 cataphyllary leaves ; 4, a zone of spathulate seed-bearing 

 leaves (carpels), originally packed together in a conical 

 form, afterwards spread out. In the centre of this head 

 or cone, representing the female blossom, is formed a new 

 cataphyllary bud, with which begins anew the whole 

 cycle of Rejuvenescence, and this is repeated as long as 

 the tree exists. f 



I will not close the examination of these points with- 

 out remarking, that such periodical Rejuvenescence con- 

 nected with the alternation of the seasons, is not always 

 combined with so decided a retrogression of the meta- 

 morphosis as in the above-mentioned examples. The 

 retrogression to cataphyllary formation, in particular, is 

 very frequently absent (but not universally) in the trees 

 of more southern regions, in which the place of transition 

 from one yearling shoot to another is merely marked by 



* Vide the 'Flora,' 1844, No. 1, t. i. 



t Vide Itlu'cdi', 'lioit. Malabar,' iii, t. xiii, xx, especially t. xvii, wLere 

 tills growing-tluougli of the female blossom is represeuted. 



