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It went on to say: While Betaillon punctured the eggs with a platinum needle and developed them by means of electric discharges, Loeb in America placed eggs of the sea-urchin in a strong solution of sea water, then in a bath where they were subjected to the action of butyric acid. Finally they were placed in ordinary sea water again, where they developed in the natural manner.
Then the young Crania adhered to the bared shell, grew and perished in its turn; after which, the upper valve was separated from the lower, before the Echinus became enveloped in chalky mud." A specimen in the Museum of Practical Geology, in London, still further prolongs the period which must have elapsed between the death of the sea-urchin, and its burial by the Globigerinae.
Then, as the coralline could not have fixed itself if the Crania had been covered up with chalk-mud, and could not have lived had itself been so covered, it follows, that an inch of chalk mud could not have accumulated within the time between the death and decay of the soft parts of the sea-urchin and the growth of the coralline to the full size which it has attained.
It should have been done much sooner had not the storms been so bad in the sea near this that, until three days ago, I was not able to procure a living sea-urchin from which to make the drawings required. . .You have made all the geologists glacier-mad here, and they are turning Great Britain into an ice-house.
"But I never have seen its like; it had just like a painter's easel in its stomach yesterday!" "Why, it's an Echinus Larva: a sucking sea-urchin! Hang it, if I had known you hadn't seen one, I'd have brought up half-a-dozen of them!" "May I look, sir?" asked the Major; "I, too, never have seen an Echinus Larva." The bearded man looks up. "Major Campbell!" "Mr. Thurnall!
In all such cases we have the living body to begin with. The egg of the sea-urchin and the egg of the jelly-fish are living beings that responded to certain chemical substances, so that a process is set going in their cell life that is equivalent to fertilization.
He removed the nuclei from sea-urchin eggs and replaced them with male nuclei. Normal individuals developed. To make things still more certain, he replaced the female nucleus with a male one from a different variety of sea-urchin. The resulting individual exhibited the characteristics of the male nucleus only none of those of the species represented by the egg.
Cases of this kind are admirably described by Sir Charles Lyell. He speaks of the frequency with which geologists find in the chalk a fossilized sea-urchin, to which is attached the lower valve of a Crania. This is a kind of shell-fish, with a shell composed of two pieces, of which, as in the oyster, one is fixed and the other free.
These creatures abound in numerous species. The star-fish has rays projecting from a common centre, which gives it its name, while the sea-urchin resembles a ball. These creatures have a well defined nervous system, and have eyes, and some of them even rudimentary eyelids.
Now it is highly important that the Doctor return to his own country to carry on his proper work which means such a lot to the animals of the world. So what we want you to do is to tell the sea-urchin to tell the starfish to tell the snail to take us in his shell and carry us to Puddleby River. Is that plain?" "Quite, quite," said the porpoises.
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