390 Miscellaneous Intelligence. 



sents but a single circular aperture belonging to a tube transparent 

 as glass, and furnished in the interior with small crowns of green 

 particles as in the Chara vulgaris. This tube contains a colourless 

 liquor and white globules of various dimensions, some of them far 

 surpassing, in size, the green globules adhering to the surface. These 

 appearances are easily perceived, without any preparation of the 

 plant, and with a common microscope. This plant has flowers, 

 in the organs of which the circulation of the sap may be per- 

 ceived in all their stages. The regular order preserved in the 

 tubes by the two series of crowns, those of the ascending, and those 

 of the descending, side is very remarkable and evident. The 

 circulations in the vessels are independent of each other, so that 

 if one is injured, the others still preserve their functions. 



Of the Pollen. The principal object of M. Amici, under this 

 head, is to describe a phenomenon, which he is anxious should be 

 verified by other naturalists, but he forewarns them that a linear 

 power of 300 is necessary for its observation ; the drawing he has 

 himself given was from a specimen magnified 1000 times. The 

 Pollen was from the Portitlaca oleracia. The figure represents a 

 globe, '2\ inches in diameter, attached laterally to a curved tube, 

 which descends vertically ; between the tube and the globe and in 

 contact with both is the superior extremity of a hair of the stigma, 

 which forms also a transparent tube, filled with small corpuscules 

 circulating slowly in it. On first observing it the author remarked 

 nothing particular, but on a sudden the globe opened, and a tubular 

 tail extended from it, which passing above the extremity of the 

 hair of the stigma returned beneath it, thus applying itself to it 

 and doubling its diameter; the membrane forming this tube was 

 very transparent. This tube was filled with globules, which after 

 circulating through it, passed into the globe of pollen, which itself 

 was full of corpuscules in motion, and fresh globules supplied their 

 places from it. The same kind of motion was observed in the 

 vessels of the stigma. This phenomenon continued for three hours, 

 after which time the corpuscules disappeared from the tube. M. 

 Amici could not decide whether they had returned to the globe, or 

 entered the cells of the stigma, or been otherwise disposed of. 



It is necessary to an observation of this kind, that the flower be 

 gathered a short time before it fades-, the interior pistil separated and 

 placed under the micros-cope ; the most favourable light is that of 

 the sun : if then the globules of pollen already adhering to the ex- 

 tremities of the haivS of the stigma, be placed at the focus of distinct 

 vision, and all humidity excluded, they will appear perfectly spheri- 

 cal, but shortly they will be seen to explode and develop the tube- 

 like tail, and the phenomena will appear as above described. The 

 effect takes place more readily as the weather is warmer. The flower 

 gathered about eight A.M., preserves for nearly three hours the power 

 of exhibiting this phenomenon. — M. Amici considers the globules 



