THE VEGETABLE AND ANIMAL KINGDOMS. 133 



cious. According to Dr. Lindley, " So entirely in the 

 simplest forms of Thallogens [an assemblage embracing sea- 

 weeds, fungi, and lichens] is all trace of series missing, that 

 in some of them their reproductive matter has been regarded 

 by certain writers as altogether of an ambiguous nature. 

 In their opinion, it is even uncertain whether this matter 

 will reproduce its like, and whether it is not a mere repre- 

 sentation of the vital principle of vegetation, capable of being 

 called into action either as a Fungus, an Alga, or a Lichen, 

 according to the particular conditions of heat, light, mois- 

 ture, and medium, in which it is placed ; producing Fungi 

 upon dead or putrid organic beings; Lichens upon living 

 vegetables, earth, or stones ; and Algae where water is the 

 medium in which they are developed. Kiitzing endeavours to 

 maintain the following propositions connected with this sub- 

 ject: 1st, the formation of organic matter can only take 

 place by means of the previously dissolved elements of other 

 organic principles ; 2nd, simple globules, such as Crypto- 

 coccus, Palmella, and Protococcus, can give birth to different 

 formations, according to the influence of light, air, and tem- 

 perature ; 3rd, we must regard all the forms of lower algae as 

 vegetations of a very simple structure, and distinguish them 

 from each other, notwithstanding that in certain circum- 

 stances they maj^ raise themselves to vegetations of a higher 

 form ; for, in other circumstances, they can exist and mul- 

 tiply independently ; 4th, the same formation may be pro- 

 duced by primitive formations of altogether different kinds." 

 " It has been said," adds Dr. Lindley, " that Algae are 

 aquatics, while Lichens and Fungi are terrestrial ; but Fungi 

 will develop in water, when they assume the form ofAlgce"(^) 

 Undoubtedly, eight so-called genera of fungi are now set 

 down as only variations of one plant (Telephora sulphurea), 

 arising from peculiar conditions of culture. 



Even in higher departments of the vegetable kingdom, the 

 revolutions have been very remarkable. Six so-called species 

 of pine are wound up into one in a recent memoir on the 

 Coniferae. The cowslip, primrose, oxlip, and polyanthus, 

 which were always regarded as distinct species, are now 



