364 EXPLANATION OF THE PLATES. 



the germ. e. Fourth stage (n. s.) ; the germ has become two-lobed, 

 or heart-shaped ; the spore-cell with its coat and the end of the tube 

 is beginning to decay, f. Fifth stage (n. s.) ; in the notch of the 

 germ, which has increased in size, a little protuberance has been 

 formed which begins to grow downward into a root and upward into 

 the first-leaf, g. Sixth stage (n. s.) ; the germ has reached its full 

 development and is beginning to decay ; the first leaf of the plant is 

 perfect, the second has made its appearance and the root is beginning 

 to branch, h. Seventh stage (n. s.) ; the germ has decayed and 

 disappeared ; the young plant, now complete, developes without further 

 peculiar phenomena. 



FIG. 3. (n. s.). A twig with a leaf, in the axil of which has 

 been formed a bud, that is a new plant connected with the original 

 plant. 



FIG. 4. A plant of the garden Strawberry (one- sixth of the natural 

 size). The parent plant a has sent out slender shoots from the axils of 

 its leaves ; the shoots, instead of perfect leaves, have scale-like organs 

 situated at a considerable distance from each other ; these shoots are 

 called runners. From the axil of each scale is developed a bud which 

 immediately strikes root and becomes a perfect Strawberry plant c. 

 In the following year the shoot uniting it with the mother-plant b 

 decays, and the latter thus becomes surrounded by a numerous 

 progeny. 



FIG. 5. A leaf of Bryophyllum calycinum (n. s.), which when 

 placed upon moist earth (damp air has the same influence) gradually 

 produces little plants in all the indentations of its border. 



FIG. 6. A longitudinal section of the pistil of the Heartsease 

 (Viola tricolor). In the hollow head- shaped stigma lie a quantity of 

 reproductive cells (pollen), which have been thrown upon it by the 

 bursting of the anthers. These cells have all become elongated into 

 tubes which creep through the canal of the style b down into the 

 germen c, and here in part enter the numerous seed-buds (ovules) 

 d existing here. 



FIG. 7. A single seed-bud (ovule) of the same plant, cut through 

 lengthways, with the whole of the tube of the reproductive cell. 

 This, a, is here, as in the Fern, enclosed in a dark coat, which the 

 tube b has broken through. The free end of the tube having reached 

 the seed-bud c, passes through its different envelopes till it reaches 

 the internal cavity, here it swells up and becomes filled with green 

 cells which are gradually transformed into the embryo, while the 

 remaining portion, with the reproductive cell, gradually decays and 



