Composite Organs of Plants. 183 



rect view of the general aspect of the epidermis; and If he ex- 

 tends his researches further, he will very probably meet with 

 varieties of structure different from any that have been yet 

 specified. Nature loves to luxuriate in varieties, and further 

 varieties have been accordingly met with. 



Mr. F. Bauer, of Kew, describes the cuticle of Doryanthes 

 hastata Correa as consisting of two or three stories of cells laid 

 one above another, and exhibiting in their aggregate aspect 

 a resemblance to that of a honeycomb. The epidermis of 

 the inner surface of the petals of Crocus vcrnus presents the 

 similitude, neither of a network of fibres, nor of stories of 

 minute cells, but of a thin and individual layer of parallel and 

 tangent reeds of unequal lengths, interspersed with multitudes 

 of minute and shining points, or molecules, and resembling a 

 front view of the false pipes of an organ. Finally, in the stem 

 and branch of woody plants, the epidermis often exfoliates, 

 and is again regenerated even if destroyed by accident; but in 

 herbaceous plants, and in the leaf, flower, and fruit of other 

 plants, the epidermis never exfoliates, and is never again re- 

 generated if once destroyed. 



The Pulp. — The pulp, or cellular tissue, is a soft and succu- 

 lent substance, constituting the principal mass of herbaceous 

 plants, and a notable proportion of many parts even of woody 

 plants. It abounds in the seed-lobes and in succulent fruits, 

 of which any one may easily satisfy himself by cutting up, 

 whether in a longitudinal or transverse direction, a bean or 

 an apple recently gathered from the stalk or tree. It is also 

 particularly conspicuous in the leaf and flower, with their foot- 

 stalk, when stript of the epidermis. Nor is it wanting even 

 in the stem of woody plants, though it is cognizable, at least 

 as a separate organ, only in the pith or in the bark of the 

 young and tender shoots, where it constitutes a thin layer im- 

 mediately under the epidermis, and forms a sort of secondary 

 integument to the plant, known among botanists by the name 

 of the cellular integument. In the leaves its colour is generally 

 green, and in the seed-lobes white; while in flowers and fruits 

 it assumes almost all varieties of shade, according to the spe- 

 cies of plant, or according to the circumstances in which it is 

 placed. When viewed without the microscope its appearance 

 is that of an assemblage of small and minute granules, im- 

 bedded in a soft and glutinous substance, as in the greater 

 part of leaves and succulent fruits. But it is only when viewed 

 minutely with a good glass that its true structure is to be de- 

 tected. Malpighi describes it with his usual accuracy, and 

 compares it to an assemblage of inflated threads or bladders, 

 containing a juice. Grew describes it under the appellation 



