Jan. 1, 1S69.] 



HABDWICKE'S SCIENCE-GOSSIP. 



were straight instead of being coiled. The lime- 

 stones of this age are crowded with immense 

 numbers both of species and individuals belonging 

 to these genera. Of them all the Orthoceras was 

 perhaps the most dreaded, partly on account of its 

 size (some of their shells being three feet long, and 

 as thick as a man's leg), and partly on account of 

 their voracious habits. Fancy them, as I have 

 frequently seen them, with their last chamber sur- 

 rounded with a fringe of long arms, each of which 

 was furnished with suckers that would indicate no 

 slight danger to bathers nowadays ! Hundreds of 

 thousands of these creatures existed. Indeed, they 

 were the scavengers of the Carboniferous seas, eat- 

 ing up everything that came in their way, and 

 perhaps not particular about preying upon a weakly 

 brother when appetite prompted them. In Scot- 

 land, in many parts of the limestones formed at this 

 time, the strata, for hundreds of feet in thickness, 

 are composed of hardly anything else but the ac- 

 cumulated shells of Orthoceratites ! 



At the bottom of the sea in which these cepha- 

 lopods lived and flourished there were gathered 

 together immense shoals of a peculiar shell called 

 Spirifera, now extinct. Scores of species of this 

 particular shell lived and died there, for it was the 

 period when the family attained its maximum of 

 existence. In fact, they occupied the place in those 

 earlier seas that cockles and mussels do now. Their 

 anatomy was very peculiar, each shell-fish being 

 furnished with a peculiar coiled-up apparatus which 

 it could protrude so as to produce currents that 

 brought to it its food. Small, but beautiful crusta- 

 ceans, of a race then fast dying out, still swarmed 

 the waters. Formerly they were known as 

 Trilobites — those of this age are christened Phil- 

 lipsia. Their family had exercised a sort of mollus- 

 can oligarchy during previous geological epochs. 

 But the Carboniferous period saw the last of the 

 race, and its limestones became their tomb. I am 

 told that the geologist knows few fossils more 

 beautiful than these little trilobites. The cream, 

 coloured matrix in which they are imbedded, and 

 the perfect and ornate characters of the fossils them- 

 selves, cause them to be greedily collected and much 

 admired. In the same sea were hundreds of species 

 of shells besides, all of which thronged together to 

 enjoy a common life ; but to mention them separately 

 would be to convert my story into a tedious detail. 

 I should be lacking greatly in memory, however, if 

 I were not to mention a most abundant and peculiar 

 family, allied to the star-fishes and sea-urchins of 

 the present day — I mean the Crinoids. The common 

 feather-star of recent seas most resembles the upper 

 parts of these extinct animals. But the tentacles of 

 the latter were longer, whilst each was subdivided 

 into branches. When at rest, these closed around 

 the body like the petals of a tulip. Again, each 

 was fastened to a jointed stem, which anchored itself 



by roots to the sea-bottom. Submarine forests of 

 these crinoids covered many square miles of the 

 rockier portions, and their graceful outlines and 

 motions in the water, as well as their bright colours, 

 were sufficient to induce admiration. In Derby- 

 shire the limestone is almost entirely composed of 

 their broken and aggregated stems. 



As these dead shells and other animal remains 

 accumulated along the ocean-floor to form a lime- 

 stone that should afterwards be easily identified by 

 their imbedded forms, almost every individual was 

 coated by minute sea-mats. No Honiton lace of 

 the present day ever excelled in grace and elegance 

 that which belonged to these lowly animated beings. 

 In the solid masses of the Carboniferous limestone 

 you may now fiud them festooning shells and corals ; 

 and few objects afford greater delight to the 

 geologist when he comes across them. The single 

 torals also — that is to say, those which did not grow 

 in reefs, but lived solitary on the sea-bottom —were 

 not inferior in beauty to any now existing. Their 

 fringe of gorgeously coloured tentacles made them ap- 

 pear like so many animated flowers ; and thus the 

 dark caves of ocean then bore many a flower that was 

 born to blush unseen. Slowly, through countless 

 myriads of years, the Carboniferous limestone in- 

 creased to its present thickness, principally by the 

 accumulation of dead shells ! The sea-water con- 

 tained more or less of carbonate of lime, which the 

 shell-fish absorbed in order to build then - dwellings, 

 just as the trees did carbon that they might form 

 wood. In this way the minute particles became 

 ultimately condensed into rock masses. Meantime, 

 the water was animated by little creatures that 

 would have evaded human eyesight, although their 

 forms were not a whit less elegant and graceful than 

 those of their larger neighbours. Their tiny shells 

 fell to the sea-bottom, and there formed a bmy 

 mud, which acted as a fine cement for the bigger 

 fossils. As time passed on, the sea actually became 

 shallower, by reason of the vast numbers of organ- 

 isms lying on its floor. The weight of sea-water 

 pressed them into a solid limestone rock, such 

 as you now behold it. Can you wonder, after 

 this, that such a deposit should take a high 

 polish when worked, or that the marble thus 

 produced should be speckled and marked by so 

 many strange forms as you see it in your mantel- 

 pieces or pillars ? 



In the shallower waters of the sea, and sometimes 

 even in the marine lagoons where the trees grew, 

 multitudes of strangely-clad fishes swarmed. The 

 largest of these, the Megalichthys, or " great fish/' 

 possessed characters which linked it to the reptile 

 family. Its teeth and jaws rendered it a formidable 

 assailant, and its powerful build and rapidity in 

 swimming made it the terror of its neighbours. In 

 fact, the "great fish" occupied a place among the 

 fishes of its time similar to that held in modern 



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