'Natural History in Foreign Countries, 473 



Hesearches on the Pollen of Plants and the ultim^ite Particles of Matter.*-^ 

 The Academy of Sciences, at their Meeting of Dec. 8., heard the report of 

 MM. Cassini, Desfontaines, Mirbel, and De Blainville, on a memoir on 

 Pollen and the Spermatic Granules of Animals, by M. Adolphe Brongniart. 

 In a former memoir on the same subject, this gentleman had detailed some 

 interesting and accurately analysed facts ; on the theory contained in it the 

 Committee had not given any opinion, but had requested the writer to per- 

 severe in his observations. In a subsequent paper, M. Raspail, an experienced 

 microscopic observer, had combated the opinions of M. Brongniart, and 

 endeavoured to demonstrate that the granules contained in the grains of 

 pollen, so far from being analogous to spermatic animalcules, are not even 

 organised bodies. After adverting to these memoirs, M. Cassini noticed the 

 opinions contained in a paper by the celebrated English botanist, Mr. Robert 

 Brown. This gentleman thinks, with M. Brongniart, that the granules of 

 pollen are endued with a distinct and independent motion ; but on various 

 theoretical points he differs from him. He has not only observed this 

 motion in the granules of living plants, but has also perceived the same pro- 

 perty in those of plants dried for a centurj', and preserved in spirits of 

 wine, and in those of mosses and equisetums living or dried ; in the mole- 

 cules obtained by triturating in water the organic tissue of animals or vege- 

 tables living or dead ; and in those obtained in the same manner from all 

 sorts of inorganic substances, as glass, granite, &c. In short, he thinks 

 that all the active molecules, organic or inorganic, are the same in nature, 

 form, and size, and endued with the same properties ; and not in the least 

 different from those observed in pollen by M. Brongniart. 



In the present memoir, which is principally devoted to the refutation of 

 M. Raspail's objections, M. Brongniart cites, in support of his own mode of 

 observation, the curious fact, that plants made to flower in winter, by means 

 of shelter and artificial heat, have generally their grains of pollen filled with 

 a mucilaginous substance, devoid of regular and moving granules ; and, as 

 these plants rarely fructify, he thence draws an inference favQurable to his 

 system. 



Thus, then, the question discussed by M. Brongniart is now debated by 

 three very skilful observers, and resolved in three different ways : for, whilst 

 M. Brongniart admits, in the interior of grains of pollen, regularly organised 

 corpuscles, of a very peculiar nature, distinct from all other bodies, analo- 

 gous to spermatic animalcules, and essentially destined to produce the 

 embryo ; M. Raspail sees nothing in these corpuscles but little resinous 

 masses, shapeless, variable, and absolutely deprived of organisation and of 

 life ; and Mr. Brown, discarding at once the exclusive opinions of both, 

 admits in all natural bodies, whether organic or inorganic, active molecules 

 of the same form, size, and nature, and exhibiting a spontaneous motion as 

 soon as they are disintegrated and plunged in fluid. 



The Committee, on the one hand, agreed with M. Brongniart and Mr. 

 Brown, that the causes to which M. Raspail attributes the motion of the 

 granules, exercise, in reality, no influence over them; and, on the other, 

 they coincided with Mr. Brown, that various inorganic bodies, triturated in 

 water, offer, if not always, at least sometimes, corpuscles whose size, form, 

 and motion are nearly the same, under the microscope, with those of the 

 granules of pollen. They also remarked, that the resemblance between the 

 active molecules of Mr. Brown and the spermatic granules of M. Brongniart, 

 furnishes strong presumptions against the hypothesis of the latter. They 

 called the attention of botanists to the singular phenomenon of apparently- 

 spontaneous motion, and asked if it might not be attributed to mutual 

 attraction and repulsion. Great difference was observed in the manifest- 

 ations of this phenomenon ; so much so, that, under circumstances to all 

 appearance alike, the granules of the same plant at one time exhibited a 

 very perceptible motion, and at another perfect immobility. 

 Vol. I. — No. 5. k k 



