U4 HYPOTHESIS OF THE DEVELOPMENT OF 



still take place in some of the obscurer fields of creation, 

 or under extraordinary casualties, though science pro- 

 fesses to have no such facts on record. It is here to be re- 

 marked, that such facts might often happen, and yet no 

 record be taken of them, for so strong is the prepossession 

 for the doctrine of invariable like-production, that such 

 circumstances, on occurring, would be almost sure to be 

 explained away on some other supposition, or, if present 

 ed, would be disbelieved and neglected. Science, there- 

 fore, has no such facts, for the very same reason that soma 

 small sects are said to have no discreditable members — 

 namely, that they do not receive such persons, and ex- 

 trude all who begin to verge upon the character. There 

 are, nevertheless, some facts which have chanced to be 

 reported without any reference to this hypothesis, and 

 which it seems extremely difficult to explain satisfactori- 

 ly upon any other. One of these has already been men- 

 tioned — a progression in the forms of the animalcules in a 

 vegetable infusion from the simpler to the more compli- 

 cated, a sort of microcosm, representing the whole histo- 

 ry of the progress of animal creation as displayed by ge- 

 ology. Another is given in the history of the Acarus 

 Crossii, which may be only the ultimate stage of a series 

 of similar transformations effected by electric agency in 

 the solution subjected to it. There is, however, one di- 

 rect case of a translation of species which has been pre- 

 sented with respectable amount of authority.* It appears 

 that, whenever oats sown at the usual time are kept crop- 

 ped down during summer and autumn, and allowed to re- 

 main over the winter, a thin crop of rye is the harvest 

 presented at the close of the ensuing summer. This ex- 

 periment has been tried repeatedly, with but one result: 

 invariably the secale cereale is the crop reaped where the 

 avena saliva, a recognised different species, was sown. 

 Now it will not satisfy a strict inquirer to be told that the 

 seeds of the rye were latent in the ground, and only su- 

 perseded the dead product of the oats ; for if any such fact 

 were in the case, why should the usurping grain be al- 

 ways rye ? Perhaps those curious facts which have been 

 stated with regard to forests of one kind of trees, when 

 burnt down, being succeeded (without planting) by other 

 kinds, may yet be found most explicable, as this is, upon 



* See an article by Dr. Weissenborn* In the New Series of " Ma- 

 gazine of Natural History," vol. i. p. 574. 



