BOTANICAL INFORMATION. 13 



will be absolutely essential to make the descriptions of such 

 minute objects intelligible, he will spare neither care nor 

 expense in rendering the plates, which will be executed 

 under his own eye, as accurate as possible. 



The engravings will be on copper, since experience has 

 proved that the delicate markings of the Desmidiece cannot be 

 sufficiently displayed by lithography. 



Upwards of one hundred species will be introduced, many 

 of them either altogether new, or now first noticed as 

 British. 



The conjugated state of the Desmidiece is interesting, some- 

 times from its resemblance to the same state in the Conju- 

 gatae, sometimes from the similarity of the spores to fossil 

 bodies found in flint, and considered by Ehrenberg and other 

 naturalists as a species of Xanthidium. On these accounts, 

 and also because few instances have been hitherto recorded, 

 it is intended to give not only full details of the process, but 

 as far as practicable, to show the different stages, by figures. 

 Examples will be taken from one or more species in each of 

 the following genera ; Glceoprium, Didymoprium, Micrasterias, 

 Euastrum, Cosmarium, Xanthidium, Staurastrum, Tetmemo- 

 rus and Closterium. 



As their animal nature has been maintained by many able 

 writers, this question will be examined, and sufficient reasons 

 produced for considering the Desmidiece to belong to the 

 vegetable kingdom. Their modes of growth and other facts 

 which may illustrate their cecojiomy, will receive particular 

 attention. 



That nothing may be wanting to the utility of this mono- 

 graph, the introduction will contain ample directions for 

 finding and gathering these minute plants, and the different 

 methods of mounting them for the microscope. 



Names of Subscribers, to whom the price will be one 

 guinea, received by the Author, Penzance, Cornwall. 



