HARDWICKE'S SCIENCE-GOSSIP. 



147 



"big," with no practical or theoretical result to 

 science — to call a colour-form var. albida, var. rubra, 

 &c., when the whole matter would be as well ex- 

 pressed in the mother-tongue by saying "a white 

 form," or "a red form of such and such a species," 

 as the case may be ? Does not all this rather tend to 

 subvert the ends of science, since it is leading along 

 the broad way to confusion ? For example, there is 

 a var. albida of Helix virgata described as " unicolor, 

 spira pauUo elatiore, d. 17, a. 11-12 mill.," and there 

 is also a var. albicans described as "a shell entirely 

 white or whitish, without markings," in the same 

 species. Whence the difference ? 



What, then, do I propose? An ink-pot is an 

 ink-pot, whether it contains red, black, or blue ink. 

 It remains an ink-pot, and nothing more. But there 

 are various shapes of ink-pots ; there are varieties of 

 ink-pots. I am not a variety simply because I am 

 taller or smaller than my friend Albert Paling, or 

 John Cook. Therefore, I would cut out for ever all 

 the named so-called varieties, which simply denote a 

 unicolorous colour-change from that in the recog- 

 nised type, and designate its characteristic colour in 

 English terms of speech. I would cut out for ever 

 and ever all the so-called varieties — major, grandis, 

 minor, parvnla, brevis and parva, and designate their 

 largeness or smallness in terms of measurement only 

 — preferably in milhmetres. But I would reserve all 

 the variety-names which denote a well-marked struc- 

 tural change in the shell from the recognised type, as 

 the vars. Burneiii, stagnaliformis, ovata, and lineata 

 of Limnaa peregi-a, and so forth. But I would not 

 recognise varieties marking only slight changes in 

 shape from the type, or from previously described 

 varieties, as the var. acuminata of L. peregra, which 

 differs from var. ovata simply and only in having a 

 smaller mouth and a more produced spire. 



Some will doubtless think my notions somewhat 



too restrictive in character, but, if carried out, they 



will stay an almost inevitable confusion. The third 



part of my paper — The Probable Cause of Variation 



— will be chiefly worked out ' on the physiological 



basis of heredity, which I reserve till later, since I 



send this forward for the purposes of discussion, and 



for the gathering together of the present-day views 



of conchological workers on this question, several of 



whom will doubtless write on the subject to these 



pages. The second part will discuss this question in 



more detail. 



( To be continued. ) 



Mitton, Stourport, Worcestershire. 



Hairs on Pup^. — All the members of the family 

 Liparidre have hairy chrysalides, viz. : — Liparis 

 ckrysorrhcea, atirijlua, salicis, dispar, and monacha ; 

 Orgyia pudibiutda, fascelina, cccnosa, gonostigma, and 

 aiitiqua ; Dcmas coryli. One of the commonest of 

 these is salicis, which has a very hairy chrysalis.— 

 F. W. Paple, Bolton. 



THE FLORA OF THE PAST. 



No. IV. 



By Mrs. Bodington. 



\Coniinued from p. 123.] 



THE immense development of apparently new 

 orders and species of mammals does not occur 

 till the Eocene Tertiary. In Europe, as is well known, 

 there is a great gap between the Upper Cretaceous 

 and the Tertiary series ; but in America they pass 

 so gradually into one another in the Laramie forma- 

 tion, that it is still a matter of dispute whether the 

 Laramie shall be called Upper Cretaceous or keep 

 its old name of Lignite Tertiary. In the Canadian 

 North- West there is no break between the Fox Hills 

 group, undoubtedly Upper Cretaceous, and the 

 Laramie ; the beds of Miocene conglomerate lie 

 unconformably on the latter, the Eocene being 

 absent in this region. Professor Nicholson says, 

 " The Lower and Upper Cretaceous rocks are sharply 

 separated from one another, from a botanical point 

 of view. The Mesozoic period is characterized by 

 the prevalence of the Cryptogamic group of the 

 ferns, and the Gymnospermic groups of the Conifers 

 and Cycads. Up to the close of the Lower Cre- 

 taceous, ;no angiospermous exogens are certainly 

 known to have existed, and monocotyledonous plants 

 or endogens are very poorly represented. With the 

 Upper Cretaceous, however, a new era of plant life, 

 of which our present is but the culmination, 

 commenced, with a great and apparently sudden 

 development of new forms. We have now an 

 astonishingly large number of true angiospermous 

 exogens, many of them belonging to existing types, 

 and along with these various monocotyledonous 

 plants, including the first examples of the great and 

 important group of palms." It is strange to think of 

 this modern type of vegetation appearing whilst the 

 "ocean was still tenanted by Ammonites and 

 Belemnites, and when land and sea were still 

 peopled by the extraordinary extinct reptiles of the 

 Mesozoic period." There are indications, however, 

 from later researches, that the development was by 

 no means so sudden as it at first appears. Poplars, 

 laurels, sassafras, mallows and willows, sedges and 

 grasses have been found in Lower Cretaceous rocks, 

 and we may safely infer that it is only the present im- 

 perfection of our geological researches which has pre- 

 vented us from finding a much more extensive flora. 



But in the Dakota group of North America, 

 Cenomanian of Europe, a magnificent flora confronts 

 us, richer and more varied than any collection of 

 plants in one region of the earth could be now, 

 owing to the peculiar conditions of climate, which 

 allowed beeches, oaks, chestnuts, palms, tulip-trees, 

 cycads, tree ferns, and magnolias to flourish together. 

 To these may be added fig-trees, eucalypti, plum- 

 trees, cinnamon trees, various species of leguminous 



H 2 



