during the Year 1 82S, 1 417 



to the circumference, and a medullary canal. Thus the organ- 

 isation of the four bundles, and consequently their growth, 

 are exactly similar to those of the ligneous stems of coty- 

 ledon plants. This unexpected fact has appeared so strange 

 to several people, that they fancied these bundles had been 

 engrafted on the stem. They were, however, undeceived by 

 a close examination. 



M. du Petit Thouars, when observing the flowers of the 

 wild poppy, was struck with the disposition of the stamina, 

 none of the anthers of which touch each other, notwithstand- 

 ing their great number. This probably arises from the regu- 

 larity with which they radiate from a common centre. In 

 some flowers, such as those of the JKosaceae, where the stamina 

 are not quite so numerous, we can trace a rectilinear arrange- 

 ment, arising from their insertion and their unequal lengths. 

 These divisions generally accord with the number of the 

 petals, and all the observations of M. de Thouars confirm the 

 assertion of Grew, that the arithmetic of nature always accords 

 with its geometry. They also prove the position of Linnaeus, 

 that the flower is but the transformation of the leaf; and 

 another, that the number five is most employed by nature in 

 dicotyledons, and three in monocotyledons. M. de Thouars 

 traces these last two to the manner in which the bundles of 

 vessels proceed from the scion into the leaves. The remark, 

 that five was a favourite number in nature, was made by 

 Thomas Brown in 1656. 



M. Adolphe Brongniart last year made some observations 

 concerning the pollen of flowers, which led him to state, that 

 every grain is an organised bladder, filled with corpuscles, 

 themselves organised, and gifted with separate movements. 

 On the other hand, M. Raspail, one of the most skilful ob- 

 servers of microscopic phenomena, has presented a memoir to 

 the Academy, declaring that these bodies are only moved by 

 external causes, and that they are resinous, or oily drops, 

 which dissolve in alcohol. M. A. Brongniart, supported in 

 his opinion by the celebrated English botanist, Robert Brown, 

 has defended his previous statement in a second memoir, and 

 repeated his experiments. The Committee of the Academy 

 have determined, that M. A. Brongniart has proved that ex- 

 ternal causes have nothing to do with the movements observed 

 by Mr. R. Brown and himself, and the Committee at the same 

 time declare, that similar movements have been clearly demon- 

 strated to them, as existing in many different bodies. This 

 phenomenon, however, varies very much, even when the cir- 

 cumstances are alike, and the question of fecundation is wholly 

 independent of these movements. i ,. 



