CONSTRUCTION OF THE CATERPILLAR. 137 



ments of a leaf, or of a flower in the bud, that Swam- 

 merdam has given figures of the parallel developments 

 of larvae and of a carnation. His selection of this flower 

 was not perhaps the most happy ; but our readers may 

 readily obtain examples by carefully dividing the un- 

 expanded buds of the rose, the lilac, the horse-chestnut, 

 the American walnut, or beans, and other large seeds 

 after they have been planted in moist earth, but not 

 left long enough to shoot into a plant. The preceding 

 figures will illustrate this better than description. Dr 

 Grew proved in this manner that flowers which blow 

 in spring are formed in the preceding year;* and Du 

 Hamel, on dissecting, in January, the bud of a pear- 

 tree, found under an envelope of about thirty leaf scales 

 eight or ten embryo flowers resembling rose-buds be- 

 studded with hairs. f 



The butterfly and the flower-bud, however, differ re- 

 markably in the manner in which they are nourished, 

 the latter receiving sap from the enveloping leaf scales, 

 the former taking food into the stomach through the 

 mouth of the caterpillar. The stomach, indeed, of the 

 inclosed butterfly is so capacious, that it fills the greater 

 portion of its body ; and requires the caterpillar to occu- 

 py almost its whole time in eating in order to satisfy its 

 cravings. When the food is digested in the stomach 

 of the insect, it passes, as in the larger animals, into 

 the small intestines ;J but it is not, as in them, col- 

 lected by innumerable little vessels which afterwards 

 run into one, (as brooks unite to form a river,) and go 

 to the lungs to be exposed to the air, supplied by 

 breathing, in order to be there oxygenated and formed 

 into red blood. Insects, on the contrary, do not 



* Grew. Phys. Veg., ii, 60. 

 t Du Hamel, Physique des Arbres, iii, 1. 

 $ See * Insect Architecture,' p. 309, D, D.; and this vol. 

 p. 198. 



VOL. VI. 12* 



