1867.] Louis Figuier. 177 



The converse of the first sentence of the preceding extract is fre- 

 quently observed. A leaf is never transformed into any other 

 organ ; but where we should expect stamens, carpels, petals, &c, 

 leaves are often abnormally developed. All the organs of the plant 

 are formed upon a plan, of which the leaf is taken as the type. This 

 doctrine of Goethe has been long recognized by all botanists. And 

 tracing the liornologues of the leaf in the various forms assumed by 

 flowers and fruit, constitutes one of the charms of botanical study 

 to the young student. 



Exhalation, respiration, and circulation in plants are then glanced 

 at by the author, before proceeding to describe the various parts of 

 the flower and their functions. 



The different kinds of inflorescence and varieties of fruits and 

 seeds come under review ; and lastly, the interesting phenomena of 

 fecundation and germination are investigated, bringing the portion 

 devoted to organography to a close. The chapter on fecundation 

 is extremely interesting, and is written in a popular style. " When 

 the existence* of sexual differences in vegetables was first propounded, 

 the discovery produced general astonishment. If the most con- 

 vincing proofs had not established it, if the commonest observation 

 had not allowed every one to verify its reality, it would certainly 

 have been classed anions: the most singular inventions ever issued 

 from a poet's imagination; but the proofs were convincing. The 

 demonstration of the existence of sexual organs in vegetables 

 became a brilliant and unexpected fact, exhibiting a wonderful 

 analogy between animals and plants, filling up in part the gulf 

 which had hitherto existed between the two great classes of organic 

 beings, yielding an inexhaustible fund of reflection and comparison 

 to naturalists and thinking men. 



" The ancients had very vague ideas on this subject. Yet we 

 leam frorn Herodotus that in his time the Babylonians already 

 distinguished two sorts of Date Palmes. They sprinkled the 

 pollen of one on the flower of the other, in order to perfect the 

 production of the fruit of that valuable tree. 



" Cesalpin, an Italian philosopher, physician, and naturalist, who, 

 in the 16th century, was professor of medicine and botany at Pisa, 

 remarked that certain sets of mercicrialis and hemp remained sterile, 

 while others were productive. He considered the first as the male 

 sets, and the second as the female. In the 17th century, Nehemiah 

 Grew, a learned English Fellow of the Pioyal Society of Lon- 

 don, published in 1682 an anatomy of plants; above all, Jaques 

 Camerarius, a German botanist, born at Tubingen, showed the pre- 

 cise use of the two essential parts of the flower, and the part that 

 each plays in producing the fecundation of germs. In a letter 

 now become celebrated, Be Sexu Plantarum, published in 1694, 



vol. rv. * p - 177. n 



