596 APPENDIX. 



the gerrnen is formed through the cup-shaped, spreading flower-stalk, which 

 is easily understood through a longitudinal section of the flower, as seen in fig. 13, 

 where e represents the cavity of the germen. 



Fig. 14. A somewhat later condition. The inner circle of the corolla has 

 appeared. Alternating with these and the most external circle we have three little 

 elevations, forming a fourth leaf-circle of the flower. 



Figg. 15, 16. Perpendicular sections of the last, in which the four circles of leaves 

 are figured a, b, c, d from without inwards. This section does not exhibit accurately 

 the centre of the corolla. 



Fig. 17. The same in much later circumstances (the whole flower was three- 

 quarters of an inch long), seen from above. The parts of the flower have been 

 cut away about half a line above the germen : d' is the leaf of the innermost 

 circle, which becomes the stamen ; d" is the leaf of the same circle, which is 

 folded together to form the style, and is already grown together by the edges ; d is 

 the third leaf of this circle, which is aborted. 



Fig. 18 represents a longitudinal section of the leaf (17 d.) seen from 

 within. 



Fig. 19. A somewhat earlier condition of the style, before the edges of the 

 leaf are grown together, as is more clearly seen in the transverse section, fig. 20. 



Figs. 21 23. Agrostisalba Schrad. Development of the Flower. 



Fig. 21. A very young ear: a, b, the two bracts (calyx Linn., glumce Auct.) ; 

 c. the flower-envelope (corolla Linn., pakcs Auct.) ; d, anthers ; e, germen. 



Figs. 22, 23. Flowers from the same ear, seen from two sides. The letters 

 signify the same in both figures : c c' c", three perfectly separate leaves of the 

 flower-envelope standing upon the same level ; c" is already somewhat larger than 

 the other two (palea inferior), c and c' grow together at a later period (pa/ea 

 binervis 1. superior) : d' d" d" the stamens. Between d'" and d" (fig. 22). is seen 

 a little wart, and at d' (fig. 23.) are seen two : the three stand upon the same 

 plane, and, like the large warts (leaves), form a nectary (tquamuUe Auct.), which 

 are not seen in the further development of the flower. The three stamens (fig. 

 22.) enclose the germen from which the nucleus of the seed-bud projects. 



Figs. 24 26. Carex lagopodioides. Development of the female Flower. 



Fig. 24. Very young condition of the female flower, seen from above : a, 

 bract cut through ; b b' b" the three at present perfectly free leaves of the 

 flower-envelopes, of which b and V grow together with one another, and form the 

 flask-shaped tube, which latter surrounds the germen, whilst the third leaf is not 

 developed. This flower-envelope encloses a carpellary leaf not yet closed, and 

 the nucleus of the seed-bud. 



Fig. 25. The same flower seen from the side : c, carpellary leaf; d, nucleus of 

 the seed-bud ; b b' b", as in fig. 24. 



Fig. 26. A flower in a somewhat later condition. The two leaves of the flower- 

 envelope b and b' are now grown together, and surround the third, b", which 

 retires in its growth, and at last entirely vanishes, c. The developing germen. 



PLATE IV. 



Development of the Parts of the Flower of Passiflora. Figs 1 4. are P. princepg. 

 The remainder P. cceruleoracemosa. 



Figs. 1 11. Development of the Parts of the Flower generally. 



Fig. 1. A very early condition of the flower (about one-fourth of a millimeter 

 in length). Around the elevation of the pith in the centre (the termination of 

 the stem) are five foliar organs (calycine leaves, sepals), already become slightly 

 irregular in their development, and in the early condition of the foliatio valvata 

 ( 134.). 



