IN THE MUD OF THE LEVANT. H 



I will now direct the attention of the Society to 

 the character, and more remarkable forms of these 

 interesting structures. 



In the lowest departments of the animal and 

 vegetable worlds, there exist several groups 

 of organisms of doubtful affinities, which have 

 consequently been claimed alike by the botanist 

 and the zoologist. Amongst the most interesting 

 of these are the Diatomaceae and the Desmidese. 

 Professor Ehrenberg has figured many of them 

 in his laro-e work on living Infusoria, as animals ; 

 for, although he occasionally asks the question, 

 " an animale, an vegetabile ?" it is easy to see to 

 which side he inclines. Mr. Dalrymple has also 

 advocated the same view with reference to some 

 of the genera. On the other hand, Kutzing, 

 Agardh, Meneghini, Berkley, Greville, Ralfs, 

 and a host of botanists, have held the opposite 

 opinion, and viewed them as early forms of vege- 

 table life. With reference to the Desraideae* 



* Though the Desmidese have less connexion with the 

 object of this paper than the Diatomaceae, the question of 

 their nature is not altogether alien. Some of the beautiful 

 stellate and hirsute spores of Staurastrum, and allied genera, 

 bear so close a resemblance to the fossil Xanthidia that some 

 naturalists are convinced of their identity. I possess spores 



