the natural Dutribution of Insects and Fungi. 57 



be shown, that in the animal kingdom the same law is followed 

 by nature ; in short, to take an instance, if it could be proved 

 that the Annulosa may either be divided into four groups, viz. 

 Ametabola, Crustacea, Arachnida and Ftilota, where this last is 

 remarkably capacious and divisible into two natural groups, viz. 

 Mandibulata and Haustellata, or that annulose animals may be 

 divided at once into five groups of the same degree, but of which 

 two have a greater affinity to each other than they have to the 

 other three — if, I repeat, this could be proved, should we not 

 be justified in affirming that the rule, so far as concerns Insects 

 and Fungi, is one and the same ? The possibility of thus distri- 

 buting the annulose animals has, however, been demonstrated 

 already in the Horce Entomologica ; and it is the way in which we 

 ought to take the rule that only now remains to be investigated. 

 In short, since only two methods* have yet been found to coin- 

 cide with facts as presented by nature, the question is, whether we 

 ought to account Fungi as divisible into five groups, or into four 

 of which one forms two of equal degree. Now I think it may 

 without difficulty be shown, from our author's own observations 

 and rules, that there is only one determinate number which regu- 

 lates the distribution of Fungi, and that five is this number. 



* The number seven might also perhaps, for obvious reasons, occur to the mind, 

 were it allowable in natural history to ground any reasoning except upon facts of or- 

 ganization. The idea of this number is however immediately laid aside, on endeavour- 

 ing to discover seven primary divisions of equal degree in the animal kingdom. It is 

 easy, indeed, to imagine the prevalence of a number ; the difficulty is to prove it The 

 naturalist, therefore, requites something more than the statement of a number, before 

 he allows either a preconceived opinion or any analogy not founded on organic struc- 

 ture to have an influence on his favourite science. He requires its application to nature 

 and its illustration by facts. As yet, however, no numbers have been shown to prevail 

 in natural groups but five, or, which is the same thing, four of which one group is di- 

 visible into two. Perhaps, indeed, the most clear method of expressing ourselves on this 

 subject is to say that, laying aside osculant groups, every natural group is divisible into 

 five, which always admit of a binary distribution, that is, into two and three. 



VOL. XIV. I In 



