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Show 25~ EXPLANATIONS. than he- namely, Dr. Lindley-has stated on ~he same subject. "At the requP.s.t," says thjs learnHl person, " of the Marquis of Bristol, the RevereDd Lord Arthur Hervey, in the year 1843, sowed a handful ,"'f oats, treated them in the manner recommended, by con6!l.ually stopping the flowering stems, and the produce, in 1844, ha~ ~een for the most part ears of a very slender barley, havIng much the appeara~1ce ~f rye, with a little wheat?.. and some oats; samples ot whtch are, by the favor of Lord Bristol, now before us." The learned writer then ad verts • to the "extraordinary but certain fact, that in ol·ch~daceous plants forms just as different as wheat, barley, 1~ye, and oats have ueen proved by the most rigorous evidence, to be accidental variations of one common form, brought about no one knows how, but before our eyes, and rendered permanent by equally mysterious agency. Then, says Reason, if they occur in orchidaceous plants, why should they not also occur in corn plants? for it is not likely that such vagaries will be confined to one little group in the ve~etable kingdom; it is n1ore rational to b.elieve them to be a part of the general syste1n of crea~ tLOn . . . How can we be sure, that wheat, rye, oats, and barley are not all accidental oil-sets from some unsuspected species?"* The reader will now be vartly able to judge of the value of the unsupported dictum of the reviewer. There are many other facts that throw a strong light on transmutation, both of plants and animals. So far from there being any decisive proof against this theory, there is no settled conclusion at this moment amongst naturalists ·as to what constit'lttes a species. ''There is," say! Profe sor Hens low, "no law whatever hziherto established, by which the limits of variation to a given species can b4 satisfai.J:v-:ily assign.ed, and until some such law be dis covered, we cannot expect preciswn in the details of sys· tematic botany."t "We have agreed," says Bicheno " that a species shall be that distinct form, originally so created, and producing by certain laws of generation others like itself. There is this inconvenience attending the use of it by naturali~ts, that it as.5~Jmes as a fact that which, in the present state of science, is in many cases a fit subject of inquiry ; namely, that species, according to ou1· defi· • Gardener's Chronicle, AJgnst, 184·1. f Maga7.lue of Zoology and .Ilotany, i., llG TRANSMUTATION OF PLANTS. nition, do exist throughout nature. It is too convenient a term to be dispensed with, even as an assumption; only ca.re shouid be taken that we do not accept the abstract term for the fact.''* Mr. Westwood, speaking of insects, says," In ve1:y extensive genera, the distinctions of species are so ntinute, that it requires the most practiced eye to separate them; and, indeed, there are some groups, the species of which are so intricately blended together, that no two entomologists are agreed as to their distinctness." According to Mr. H·aldeman, author of a learned work on the fresh-water mollusks of A1nerica, "There are distinct species in that class-among the U nionidre, for example [and this is a remark applicable to other departments of the animal kingdom,] actually difiering less from each .other than the known varieties of certain variable species which a I..amarkian might suppose to be of so recent an origin as not to have yet become settled in the possession of their proper diagnostic characters. Indeed, notwithstanding the assumption to the contrary, by authors who have little practical acquaintance with the details of natural history, the proper discrim1nation between species and variety, is one of the greatest difficulties which the naturalist has to encounter; and he who is successful in this department is entitled to a rank which comparatively few can attain."t Of the extent to which modifications may be carried by palp~ble exterr:tal conditions, I rnay now: supply_ a few illustratwns. It IS well known that fungi and hchens attain to very different appearances in different situations, in conformity with different conditions. Fries, we are told, "asserts that out of the different ~tates _of_ one species (telephora sulphurea) more than eight distinct genera had been constructed by different authors. It would seem, then, that the absolute number of species among the funO'i is not nearly so great as has been usually sup""' osed, ~nd that the kind produced by a decomposing infusion, or a bed of decaying solid matter., will depend as much upon the influence of the 1natenal em played as upon the genn itse~f which is the subject of it.t . Amon()" the questions proposed by the Academy of Set ences at;:,Haarlem, in 1839, was one upon the followir.g " Linnrean Tran&actions, xv., 482. t Boston Journal of Natural History i Carpenter's Physiology, p. 62 |