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Show 248 EXPLANATIONS. . ach the existing order ot ganic development hll.w~ r·~h be able to juc.:ge of the things " The re~der ~~ll ur tine: the zoology of the tercandor of the re.viewe~ 1Jsae~h t 0 it shows exactly those tiary, when he IS remi? e . a rlom which might have new portions of the ~g.1 ma~0k1t~~ theory of development. been expected, aeeOI •n 1 g f nd faint traces of mam- Her~tofore, we have ~~ey acf~!d in abundance, mammalia maha; but now ~hey f the vertebrated form As far being the crow~I~g c~assc~ncerned, it is incontesta?ly a as class, there ore~ 1 ~ic develo ment." B11t this IS not "regular h~vne ~~~~'~e reptile f~·ms of the secon~ary a pall. "YeO' the cetacean character; and now thet e Is an proachmo ·of the a uatic mammalia, as well as of th~se abundance d q which are universally classed With land ~~~!Yfo~~1:sof that order' the·se being the only suitde t'5ome o ,. h. h my ideas of development ·would lea of creatures w IC • 1 Here I must meet the re-ne to expect at !hts P ac~. He admits the dinosaurs to riewer on a special groun · 1 . but "they l n the nearest approach to mammas' \l~v; l~e " he says. (" if we are to trust to geology,) ages te aV\ ay, d of the chalk." These mammals ha':e, )efore the ,~n zooloO'ical base to rest upon;" th~t Is, heref?re, no f obetween them and any such animals ~here lS no connec ton use there is an interval in the cretaiS the anwsa.urs, b~~ah ives neither these forms nor any .!eo us for~ahon ~ ol~ lfle fact is admitted by Professor tnterrned~ate. ... t system appears to have been A t d that the ere aceous . . t . ns e ' t ·t by depos1ts 1n deep wa ei, " formed, for the mos f·ai ' f it not fa'r from the zero and a .con~if~a~ze ~~J~\~i~ he states with a particular of antma ~,e. f Professor Edwatd Forbes's re-reference. to the resultsS o We therefore have a satis-searches In the ~gean ea. earance of [ol·ms inter-fact~ ry explanatior\ of th~ ~~;:~~ls in the chalk, without m~dtate !o thf' rep 1 es an ith our reviewer, that the latter betng dnven to suppose, wf · llife But no such fact were a creation de novo ? anlma . as this di~l it snithour revledwetrotsoaysta~;~re as old as pachy- " C vora " e procee s ' · arn• . ' we have any evidence bearmg derms. As ~ar, at lde~.t, a~a (monkeys) are found in this on the questwn, an tma lt"f · th upper end d. . . thus contradictinO' and stu 1 ytng e. . oflV eulSrt aount-hor's gran d creat 'ov scale " There IS here, m 1 e -~ • Ansted'• Geology, 1., 502. T Elt TIA R Y FOSSILS. 249 reality, no stultification except in the c1·itic's own mind. It was not my scale which he refers to, but Dr. Fletcher's; adopted into my book, not as a plan of the actual proces~ of rlevelopment, but as a general indication of the comparative organization of the animal ordel's. I do not consider the assumed contemporaneousness of the carnivora and monkeys (which the reviewer erroneously call~ bimana) as at all contradictory of a true development theory, for I regard them all as distinct Jines of development, which might well advance to a certain stage (namely, that of the terrestrial mammala) about the same time. I am not, how·ever, entitled to blame the reviewer for thi"' objection, as the idea of a development in a plurality of lines must be new to him. "As we ascend," he says, "towards the middle divisions of the [tertiary] series, there is a development of nature's kingdom, nearer .and nearer to living types. But it is not a development after our author's scheme. It folows the law of he rise, progress, and decline of the fan1- ilies of the older world, already pointed out. We have no confusion of genel'a and species, and no shades of strueture to make dim their outlines." Now there is here an acknowledgment, in which all geologists accord, of a constant gradual approach to li vi11g types. Is not this, in itself, a fact speaking strongly for some simply natural procedure in the origin of the pn~sent tribes? A change goes on from one set of forms to another, ir the sarne way as one human generation is changed for another-namely, by the withdrawal of some and the addition of others, until at length the whole personnel of one age is superseded by that of another. The removal of old species is the result, by our critic's own showing, ·of law; and lavvs for the extinction of species are in opero.tion at the present day" Can we well suppose the rise of the new species to be a phenomenon of an essentially different character? for here is the whole question at issue. I say no -any ideas I have ever acquited of philosophy, as an expression of our ascertainment of the order of nature or provIdence, forbid me to form such a conclusion. A "confusion of genera or species" is not to be presumed; there is no need for a shading of structure to make dim their outlines. I suggest that a line of organization analogous to the progress of the embryo of an elevated species had passed in the course of time through its appointed stages 20 |