'252 PHILOSOPHICAL TRANSACTIONS. [aNNO 1765. 



figured by Mr. Miles ; however, as some delineations were made of them as they 

 appeared to us, they will accompany the other drawings (figures 25, 26, 27, 28, 

 29, 30, 31, 32, 33, 34, 35, 36,) and may serve to confirm Mr. Miles's account 

 of them. 



In the male flowers of Marchantia polymorpha, Linn, the grains of pollen 

 were obsei-ved in a thick tuft of hairs, where they seemed rather to have lodged 

 themselves accidentally after their dispersion, than to be affixed to them as they 

 are described by Linnaeus, (farina crinulo affixa. Gen. Plant.) These hairs, 

 viewed with the microscope, had a remarkable appearance, each hair consisting 

 of a double chain, and each chain being composed of round bodies, placed at 

 regular distances from each other, and connected by a thread. The two chains 

 are so close together, that the bodies touch each other in pairs, the whole making 

 a regular figure. After compressing one of these hairs between the talks, the 2 

 chains seemed to have twisted round each other, and to exhibit an appearance 

 somewhat resembling the cable of a ship. Of the use of these hairs in the male 

 flowers, we could form no conjectures. The figures of them will be found 

 among the drawings (figures 37, 38). 



Explanation of the Figures in Plate 6. 



The generic and specific names here used are the Linnaean. The numbers fol- 

 lowing the description, show how many times the object was magnified in 

 diameter. 



Fig. 1, A grain of the pollen of Hibiscus Syriacus: magnified 512 times. — 

 Fig. 2, The same, with the impregnating corpuscles forced out by compressing 

 the talks: magnified 512 times. — Fig. 3, Some of the same corpuscles separate 

 from the grain, and more extended in length, which was supposed to arise from 

 their adhesion to each other, though the division was not perceptible: magnified 

 512 times. — Fig. 4, Grains of the pollen of Mirabilis lalapa, with the impreg- 

 nating corpuscles seen within them: magnified 72 times. — Fig. 5, A grain of the 

 same: magnified 512 times. — Fig. 6, 3 grains of the same sticking together: 

 magnified 1280 times. — Fig. 7, Corpuscles of the same, viewed separate: mag- 

 nifkd 1 280 times. — Fig. 8, A grain of the pollen of Cucumis sativus, with the 

 corpuscles within it, and some on the outside, that had been forced out: magni- 

 fied 192 times. — Fig. 9, Grains of the pollen of Bignonia radicans, with the 

 corpuscles within them. — Fig. 10, A grain of the same: magnified 1280 times. 

 — Fig. 11, Corpuscles of the same, viewed separate: magnified 1280 times. — 

 Fig. 12, A grain of the pollen of Gomphraena globosa, compressed: magnified 

 1280 times. — Fig. 13, Grains of the pollen of Bryum, with the corpuscles 

 within them: magnified 1280 times. 



The same corpuscles were seen in the pollen of Atropa, Hyoscyamus, Scilla, 



