[2731] “Carnosæ frondis his natura.”
[2732] Many species of the medusæ, Cuvier says, and other animals of the same class, the physalus more especially, cause an itching sensation in the skin when they are touched. This is noticed also by Ælian, Hist. Anim. B. vii. c. 35; and by Diphilus of Siphnos, in Athenæus, B. iii.
[2733] This is true, Cuvier says, and more especially with reference to the actiniæ. They have the mouth provided with numerous fleshy tentacles, by means of which they can seize very small animals which come within their reach, which they instantly swallow.
[2734] Cuvier says, that this is the case more especially with the medusæ and the physali.
[2735] “Ora ei in radice.” Aristotle, however, says, Hist. Anim. B. iv. c. 5, and B. viii. c. 3, that the sea-nettle has the mouth situate ἐν μέσῳ, “in the middle of the body.” Hardouin attempts to explain the passage on the ground that Pliny has made a mistake, in an endeavour to suit his similitude of a tree to the language of Aristotle. Cuvier says, that there exists one genus or species of the medusæ, which appears to feed itself by the aid of an apparatus of branches, and is divided into such a multitude of filaments, almost innumerable, that it bears a strong resemblance to the roots of a tree or vegetable. It is this kind, he says, that he has called by the name of “Rhizostomos.”
[2736] Aristotle, Hist. Anim. B. viii. c. 3, says the same; though, on the other hand, in the Fourth Book, he says that the animal has no excrements, although it has a mouth, and feeds.
[2737] Cuvier remarks, that there are a great many more than three kinds of sponges, but that Pliny here is only enumerating those which were employed for domestic use.
[2738] In the singular, “tragus,” from the Greek τραγὸς, a goat, on account of their strong smell, which they contract from the mud and slime in which they are found.
[2739] Probably from the Greek μάνος, “rare,” “in small quantities;” in allusion to the comparative rarity of this kind of sponge.
[2740] A term merely used, as Cælius Rhodiginus says, to denote the strength of its texture.