The organic vision of Hélan Jaworski

to be loved in spite of them. The enamel of the mollusc shell is reproduced in our teeth—teeth which with some animals develop into tusks and further into horns, all secondary manifestations.

The fishes individualise the whole skeletal function. The vertebrae which appeared as ‘milk vertebrae’ in the starfish reappear interiorised in the fishes. However, there are two types of fishes, the cartilaginous ones and the bony ones. The cartilaginous fishes, like the rays and sharks, have cartilaginous skeletons but bony scales, while the bony fishes have ossified skeletons and cartilaginous scales. No fish has achieved complete interiorisation of its bony structure.

If fish are skeletons swimming free in the sea, the Crustaceathe lobsters, crayfish and crabs—are the apotheosis of limbs. Intermediate on the biological tree between the plants and animals, interiorisation is less marked in them, and so they keep their bony skeleton outside. Their appendages can undergo all manner of modifications, but are basically limbs with the pincers of crabs and lobsters foreshadowing hands.

When we come to the reptiles it is not difficult to see what they individualise. Snakes are veritable intestines served by organs. They strike the digestive note. They do not lose their legs due to lack of use but to the increased demands of digestion, and their creeping realizes locomotor peristalsis. In snakes the vertebral column has become unified and the waist and sternum have disappeared in order to facilitate the ingestion of huge meals. They can open their mouths to an incredible extent and, like the boa, can swallow animals much larger than themselves. The boa, having killed his prey by crushing it, will then sit placidly and defencelessly digesting it—slowly—so slowly that part of the prey will be digested before the whole has been swallowed. Among the reptiles we find that strange creature the tortoise. He is a reptile, but, whilst the snake looks like an intestine and is easily assigned to the digestive system, the tortoise, at first sight, does not appear to fit in. Now the most outstanding feature of the tortoise is his carapace which, in the giant sea turtles is incomplete, in the Nile turtle is cartilaginous and in the luth is just hard skin. So the hardness of the carapace, which we are

accustomed to since we kept tortoises as pets, is not an essential

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