HABDWICKE'S SCIENCE-GOSSIP. 



219 



notorious for bringing forth their young in a half- 

 gestated condition. When you ascend higher in 

 the Oolitic series, through the more purely marine 

 deposits, where, of course, you would not expect 

 to find the land creatures well represented, and 

 come to the Purbeck beds, then you will be 

 astonished at' the large number of species of 

 marsupials, and the great modification and adap- 

 tation in their habits which had taken place. The 

 streams enteriug the lakes where the Purbeck 

 marble was formed were much more likely to carry 

 the carcasses of these dead marsupials there, and 

 therefore the bottom of that lake was more likely 

 to be a richer cemetery of their remains. 



Some of the oolitic strata are much more favour- 

 able to the preservation of organic remains than 

 others, and these invariably give us a glimpse of 

 animal and vegetable life which, although of a 

 much lower organization on the whole than the 

 present, was yet admirably adjusted each to the 

 other. Thus, the fourteen species of marsupials 

 above mentioned were all obtained from a thin seam, 

 three or four inches thick, in the Purbeck series, 

 and from an excavated area of about five hundred 

 square yards ! Of all these rich fossiliferous de- 

 posits, however, perhaps the most interesting is 

 at Solenhofen, where there occurs the stone of that 

 name, much iu use now, I am told, for lithographic 

 purposes. The sediment of which it is composed 

 is very fine, so that the quality which gives it its 

 economical value to man is exactly that which has 

 rendered it such a splendid sarcophagus for the 

 fossils of the oolite. Porty yeai's ago there had 

 been obtained from this one deposit no fewer than 

 between two and three hundred species of fossils, of 

 which seven species were those of flying lizards, or 

 Pterodactyles ; six species were those of huge sau- 

 rians ; three were tortoises ; sixty species were fish, 

 forty-six were crustaceans; and twenty-six were 

 insects, which had probably been blown from the 

 land by the breezes, and eventually found a watery 

 grave and an immortality they never dreamt of. 



I have already spoken a little of the peculiar vege- 

 tation of this period— of the Cycads and Zamias and 

 Tree Perns, which had taken the place of the Cala- 

 mites, Sigillaria, and Lepidodendra of the Carbo- 

 niferous epoch. Besides these, there flourished 

 other plants, now regarded as characteristically 

 Australian, of which the Araucarian pines are ex- 

 amples ; several species are found in the Inferior 

 Oolite, whose cones showed that they lived and 

 flourished not far distant. Then, again, in the so- 

 called " dirt-beds " of the Portland stone, and also 

 of the Purbeck beds, you have evidences not only 

 of old land surfaces, but also of the dense vegeta- 

 tion which covered them. These "dirt-beds" 

 plainly indicate the extended period duriug which 

 these old cycadian and pine forests grew. Their 

 3:emains are now found silicified, their trunks and 



stems lying recumbent amid the " dirt," whose fresh- 

 water shells tell you how it had been' the shallow 

 bottom of a lake before it was a forest-bed, and that 

 it was there its rich black soil accumulated ! The 

 Cycads are flattened somewhat by the pressure of 

 the overlying beds, so that their bracts or scales 

 give them a peculiar appearance, which, I am told, 

 has earned for them among the quarry men the name 

 of "Birds' Nests." 



As you are perhaps aware, the sea was still the 

 home of the great fish-lizards, Ichthyosaicrus, Plesio- 

 saurus, &c. On the dry land the reptile family was 

 represented by an abundant group, which goes under 

 the general name of Dinosauria, or " terrible rep- 

 tiles." Judging by the size of some of them, this 

 name was not badly earned. But by far the most 

 characteristic feature about these huge land reptiles 

 was their near anatomical relationship to the birds ! 

 You hear a good deal of foolish talk now about 

 "missing links," and those who make use of it little 

 know that all the fossils are, more or less, of this 

 nature, and fill up gaps in the natural history classi- 

 fication. Some of the reptiles of which I am speak- 

 ing walked on two legs, like great Cochin China 

 fowl, and with their hind quarters much more 

 strongly developed than their fore limbs. In this 

 respect they resembled, amongst the reptilia, the 

 position of the kangaroo, which, as everybody knows, 

 generally uses only his huge hind legs, his fore limbs 

 being much smaller and weaker. One of these land 

 reptiles, named Compsognatlms, whose remains have 

 been found in the Stonesfield slate, and which was 

 only about two or three feet in length, is the nearest 

 approach, in its general structure, to birds of any 

 yet made known. As you are aware, all reptiles are 

 egg-bearing in their habits, and the fossd eggs of 

 the oolitic reptiles have been met with, showing that, 

 so long ago as the Oolitic age, this class had the same 

 habits as their diminutive representatives of the 

 present day. But what is very remarkable is, that 

 whilst the reptiles of this period had bird-like cha- 

 racters, some of the birds had reptilian peculiarities ! 

 No doubt you are aware that these two great groups 

 of animals, birds and reptiles, follow each other in 

 ordinary classification. They do so in order of time, 

 the reptiles first, in their lowest grade as Amphibia 

 (Labyrintliodonts), which gradually rise to a higher 

 standard, until they assume features which, as I 

 above remarked, now belong wholly to birds. Singu- 

 larly enough, the true birds follow soon after, and 

 the first specimen you meet with shows, in the 

 structure of its tail-bones, &c, that it had borrowed 

 some of the anatomical peculiarities of the reptiles ! 

 This strange bird is now known as the Arcliatopteryx, 

 and its bones, and even feathers, have been found 

 beautifully preserved in the Solenhofen stone. Here 

 you have, at any rate, a meeting-ground on which 

 two of the great divisions of the animal kingdom 

 exhibit their mutual descent. It is a suggestive 



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