42 VEGETABLE ORGANS. 



examined, from their large size, in most of the softer 

 fruits, as that of the snowberry or the cucumber. 



As the ovary or fruit approaches maturity, the 

 petals and stamens wither and fall off, the calyx often 

 remaining, and being sometimes adherent to the 

 ovary, at others free or unattached to it. 



Seeds. During the ripening of the fruit, the seeds 

 contained within it are gradually becoming further 

 developed. 



The seeds themselves are covered outside by a skin 

 or coat called the testa (testa, a shell) . This is re- 

 markable for frequently displaying various kinds of 

 figured patterns, consisting of raised networks, ridges, 

 little knobs or tubercles, &c. Examples of these may 

 be found in the seeds of the poppy (PL I. fig. 27), 

 mignonette (fig. 29), and chickweed (fig. 51). 



Some seeds are winged, as it is called, i. e. fur- 

 nished with an extension of the testa beyond the 

 margin of the seed. This not unfrequently consists 

 of aggregated fibre-cells, the spiral fibre being very 

 distinct, as in the seeds of Eccremocar pus scdber 

 (PL I. fig. 52). In the seeds of another curious plant 

 in this respect, viz. Collomia grandiflora, the fibre- 

 cells are separate, so as to resemble hairs, and very 

 mucilaginous, and in the dry seed are closely pressed to 

 its surface. If a portion of the testa of these seeds, 

 which can be procured at the seed-shops, be cut off, 

 laid on a slide, a cover applied, and when the object 

 is in focus, a drop of water be added, in a short time 

 water softens the mucilaginous walls of the cells, the 

 power of the spiral fibres comes into play, and the 

 cells expand so as to form a very interesting object; 

 the cells, in their expansion, apparently writhing like 

 so many minute worms (PL I. fig. 35). 



The seed itself, which is contained within the testa 

 or seed-coat, consists essentially of the young plant or 

 embryo. This is composed of three parts, viz. the 

 plumule (plumuktj a little feather), or the young stem ; 



