onjKCTS Fon the MicRoscorE. 335 



VEGETABLES. 



Seeds of Plants afford many pleasing objects, as well as the leaves, 

 8cc. : tlicy should he gummed to paper, as directed tor Insects. 



Moss. — This, in the winter months, should always he collected and 

 carefully examined, as it not only furnishes many curious subjects 

 of itself, but likewise harbours many very beautiful insects, minute 

 shells, &c. 



Farina or the Pollen of Plants affords some curious subjects, and is 

 well deserving of a further investigation. In the sixth volume of the 

 Transactions of the Linnean Society is given an Account of a JWicro- 

 scopicul investigation of several species of Pollen, with some Remarks and 

 Questions on the structure and use of that part of vegetables. By Luke 

 Howard, Esq. from which the following is extracted. 



" I began my observations," says Mr. Howard, " with the Hazel- 

 tree {Cori/lus Avellana). On a calm dry day I shook ofY some of the 

 pollen from the expanded catkins upon a clean piece of writing-paper: 

 I also gathered some of the catkins and female buds. These [ viewed 

 separately on a clear plate of glass, usually transmitting the light 

 through them from a speculum below, and with different magnifying 

 powers, preferring those which, without enormously enlarging the ob- 

 jects, gave a clear view of die stiucture and position of several at once. 

 " 1. Con/lus Avellana.— Anthers furnished with transparent horn- 

 like appendages. Pollen crumbles from the surface, and is sometimes 

 so alnindant as to fall in a visible cloud on the slightest motion of a 

 branch. To the naked eye it is a line yellow po\\der. A few grains 

 laid on the glass plate and viewed with the lens, No. ■! ; some appear 

 of an irregular angular shape, opake, except in one or two parts, where 

 light passing presents the appearance of a perforation ; others nearly 

 spherical, the surface divided by depressed lines into a number of con- 

 vex facets. The transparency of these is such, that they rellect the 

 image of a small object held under tliem, as well as a drop of liquid. 

 On repeating the examination, the former are found to come from the 

 most mature anthers, and to differ from the latter only as a raisin does 

 from a grape. A clear drop of distilled water being put on the glass, 

 both kinds imbibe it with the avidity of a sponge, at the same time 

 distending and spreading abroad in the water, but without any motion 

 further than that which this expansion causes. When saturated with 

 the water they remain at the bottom, clear as the liquid itself, and all 

 alike distended to a bulk many times greater than their original one 

 in a dry state. They are now seen to he multilocular capsules, having 

 septa in various directions within them, the union of which with the 

 external membrane apj)ears at the angles in the dry state, and at tlu: 

 depressed lines in the wet. 



