HARDWICKE'S SCIENCE-GOSSIP. 



251 



Vinca major. A bright pink cistus adorned the 

 hillsides, and an elegant orchis with blue and yellow 

 flowers (allied to apifera) flourished in the most arid 

 situations. Down in the deep channel of the Darro, 

 Adiaiitum capilhis- Veneris fringed the damp rocks 

 with its delicate fronds. The only other fern I 

 noticed in Andalusia was Cderach offi-cinanon, and 

 it was much less luxuriant than we find it in 

 Somersetshire. 



At San Fernando, on the sandy common, there 

 was abundance of a beautiful pale mauve flower, 

 allied to Staticc limoniuni, but larger and finer. 

 Everywhere the scarcity of Umbelliferae was marked, 

 'but the Compositse were numerous. Our chrysan- 

 themums (or close allies of them) were abundant. 

 The scarlet pimpernel was common by the banks of 

 the Guadalquivir, and also a bright blue species. 



Large pale Antirrhinums flourished on old 

 walls, as on the ramparts of the Alhambra and the 

 ■old bridge at Toledo. 



An Englishman sighs for large forest-trees. 

 Interminable olive groves cover the hillsides. The 

 Ilex is equally abundant, and more handsome, but 

 •of the same tint, a glaucous hue, the prevailing 

 colour of vegetation in Spain. A peculiar grace 

 .is often imparted to vegetation by the elegant 

 waving stems of the sugar-cane. But though the 

 English botanist in Spain is charmed with the variety 

 ■ of novel plants, with the gaiety of the wayside 

 flowers, and the striking outlines of cacti, palms, 

 and aloes, he meets with such vast tracks, bare of a 

 single blade of grass, that he cannot fail to return 

 with immense satisfaction to the green lawns and 

 rich meadows of his native country. 



Wm. C. Hey. 



A CHAPTER ON FOSSIL WORMS. 



DARWIN has recently shown how geologically 

 important is the common earth-worm. Doubt- 

 less a biologist as intimately acquainted with the life- 

 histories of other insignificant creatures would be able 

 to prove that the most insignificant of them plays 

 some part or other in geological operations. They 

 may not be founders of continents, like the Foramin- 

 ifera ; but the world, as we find it, would have been 

 different in some way or another if they had not 

 existed. 



A worm is the lowest member of a sub-kingdom of 

 animals on which perhaps more changes have been 

 rung than on any other. It is an annulose, or ringed 

 animal. It forms the foundational structure which 

 may be modified according to circumstances, into a 

 lobster, crab, scorpion, spider, butterfly, beetle, bee, 

 dragon-fly, cockroach, or house-fly ; besides other 

 creatures which crawl, fly, or swim. It may through- 

 out life retain the primitive structure which we are 

 .acquainted with in the common earth-worm or lob- 



worm ; or this may be but the first stage in a series 

 of subsequent improvements and modifications, as in 

 the grub-like larvae of the bee and beetle, or the 

 caterpillars of the moth and butterfly. 



Just as the worm or annelid type is largely a funda- 

 mental one, so is it one of the most ancient, geologi- 

 cally speaking. In rocks, where traces of neither 

 mollusc nor zoophyte are visible, tracks of ancient 

 sea-worms have long been known. No other creature 

 can claim such a geological immortality. Not even 

 foraminifera are more eloquent or trustworthy wit- 

 nesses of the slowness with which certain deposits 

 were laid down than they are. In all marine forma- 

 tions, from the Cambrian to the latest Tertiary, sea- 

 worms have left abundant proofs of their existence. 



We are aware that many of the so-called "worm or 

 annelide tracks," in Silurian rocks, such as those de- 

 nominated Chondrites or Cruziana, may have been left 

 by creeping mollusca or crawling Crustacea. But in 

 the absence of the solid parts of these creatures in the 

 fossil state, it is safer to assign such tracks to worms. 

 In deposits where fossil univalves and crustaceans are 

 actually met with, such tracks may have been left by 

 them. Still, the careful student cannot but be aware, 

 from his quiet study of any low-water mud or sand- 

 flat at the present day, that for one track left of 

 crustacean or mollusca, ten are left by sea-worms. 

 In short, they are the great track makers, as well as 

 sand-diggers, and we may safely give them this 

 position without minimising the importance of the 

 markings left by other animals. 



If subsidence of certain parts of the sea-floor were 

 not accepted as a geological and geographical fact, 

 sea-worms would prove it more than any other 

 animals. For when we find such rocks as the Long- 

 mynds composed of strata, all more or less of a 

 similar physical character and composition, on whose 

 upper surfaces are innumerable tracks of sea- worms 

 for at least one mile in vertical thickness, no other 

 theory could account for the conditions under which 

 they had been formed than that which declares the sea 

 bed was slowly subsiding at about the same rate that 

 the sediments were accumulating. Moreover, the same 

 worm- tracks more or less indicate the depth at which 

 such deposits were formed, for we never find these 

 markings in strata of deep-sea origin, and the 

 supplementary evidence of the ripple -marks so fre- 

 quently occurring in worm-tracked strata, is confirma- 

 tory on this point. 



Geology has little or nothing to say concerning 

 terrestrial worms, unless it refers to their physical 

 action in modern times. We are not aware of a single 

 species which can be safely referred to the same 

 habitats as our common earth-worms, although we 

 have little doubt this class has been in existence 

 perhaps during the entire Tertiary period, if not longer. 

 We have therefore only to do with sea-worms. These, 

 as we now know them, may be divided into two 

 groups, those which crawl or swim about (as the lob- 



