SHAPES OF CELLS. 13 



observation, and we shall notice these stomata more par- 

 ticularly when the slides are described. 



The origin of every plant is a single cell. The per- 

 fection of a plant, from the tiniest moss to the loftiest 

 oak, is in a countless multitude of simple cells containing 

 various substances needful for its growth, and of an infinite 

 variety of shape and substance : for some cells are very 

 thick ; some are dotted, to allow of the circulation of air in 

 the deep recesses of the stem ; some have variegated walls 

 produced by its secondary deposits, like fibre coiled around, 

 and these fibro-cells are abundant in some plants. We 

 have them from the Oncidium and Opuntia. Some cells 

 of spiral fibre act as trachea or breathing organs, or give 

 lightness and elasticity to a stem. They are abundant in 

 strawberry leaves, vine leaves,, rhubarb stems, spinach, and 

 there are beautiful examples in the slide of spiral cells from 

 the balsam. Much more can be learnt from the examina- 

 tion of the fresh plant, because of the difficulty of preserving 

 cells and their contents. Is it not wonderful to think of a 

 little plant having its store chambers secreting starch, sugar, 

 gum, oils, raphides, colouring matter aye, and beautiful 

 crystals floating in the cell-fluid, or suspended, as are the 

 cystolithes, in the cell-chambers of the nettle tribe ? 



The very knowledge that such things are, and that they 

 may be seen in an infinite variety, will lead us first to look 

 at these slides understandirigly, then to seek further by 

 examination of living plants. This will induce us to study 

 such books as Quekett's ( Histology/ 'Carpenter on the 

 Microscope/ 'Mohl on the Vegetable Cell/ ' Schacht on the 

 Microscope/ ' Uriger's Letters/ &c., &c. Then we shall see 

 our microscope worthily, and our cabinet of objects will 

 cease to be a mere toy. 



SHAPES OF CELLS. 



As the object of this little book is to excite and not to 

 satisfy the desire of an inquiring mind, let me here 

 suggest that it is well to prove all things ; and before you 

 quite believe that every flower and plant is made up of 



