64 Mr. W. S. Macleay on certain general Laws regulating 



groups of equal degree. In Protophyta fructification is secon- 

 dary, and the thallus essential ; whereas in Fungi it is quite the 

 reverse. According to our author the first-born of Flora may all 

 be accounted as essentially roots, and representing the mode of 

 nutrition ; while every fungus is as truly and representatively 

 connected with fructification and reproduction. Throwing aside 

 other considerations, we may perceive the analogous groups of 

 the animal kingdom to be likewise constructed on a similar plan. 

 Each of the Acrita, for example, imbibing nourishment at every 

 pore of their surface, internal or external, is essentially a sto- 

 mach, while the situation of the singular ovaries of the Radiata 

 cannot fail to remind us of the importance and position of the 

 sporidia in Fungi. The umbellate Medusa, the Echinus, the Js- 

 terias, and the Priapulus have all their representatives in myco- 

 logy, of which the genera Lycoperdon and Phallus are noted 

 instances ; so that the analogy of the Radiated animals to Fungi 

 is complete ; and we thus have in organized matter the following 

 two series of groups connected by affinity and analogous at their 

 corresponding points. 



Animalia. Vegetabilia, 



Acrita ...,,. Protophyta. 

 Radiata . ... . Hysterophyta. 

 Annulosa . . . . . Monocotyledonea. 



Vertebrata Dicotyledonea. 



^ Mollusca . . . . . Pseudo-cotyledonea ? Agardh*. 



Con- 



* This last department of the vegetable kingdom, Pseudo-cotyledonea, has been de- 

 fined by M. Agardh in the sixth part of his Aphorismi Botanici, which is dated De- 

 cember 1821. According to him it embraces the Musci, Hepatica and Filices of Lin- 

 naeus ; and in page 76 of the sapie work we find a comparison made between these 

 plants and Amphibia, which is nevertheless much stronger when applied to them and 

 the Mollusca, " Pseudo-cotyledonete Amphibiis non dissimiles, humum perreptatit 



vel 



