144 OEIGINAL AETICLES. 



pent.* Some creatures, on the other hand, get their food in the water, 

 and are unable to li\'e out of it, and yet admit neither air nor water, as 

 the jelly-fish and the testaceous molluscs. Of aquatic animals, some 

 belong to the sea, some to rivers, some to salt-water marshes, and 

 some to fresh-water marshes, as the frog and the cordylus.'f Of 

 marine animals, some belong to the deep sea, others to the shores, 

 others to the rocks. Of terrestrial animals, some admit and eject 

 the air, which is called inspiring and expiring, as man, and all the 

 land animals which possess lungs ; others do not admit the air,]; 

 although they live and get their food on the land, as the wasp and 

 the bee and other insects. By insects I mean such animals that 

 have incisions on the body, whether on the upper parts alone, or ou 



* vSpoQ, perhaps the common ringed snake, Natrix torqnata, which has a wide 

 geographical range, and was doubtless known to Aristotle, tliough other water-loving 

 opliidians may be comprised under the term, (see ii. 12. § 12.) 



f Kop^D/Xog. Commentators and naturalists have long been in doubt as to what 

 animal the Cordijlus rcjiresents. Its characters as given by Aristotle arc the follow- 

 ing — It is a quadraped both aquatic and terrestrial in its habits, possessed of gills, 

 but destitute of lungs, and is the only known instance of an animal having at the 

 same time feet and gills [De resplrat. x.) ; it swims with its feet and tail, which 

 latter organ is somewhat like that of the glonis, (^Silurus f/laiiis?) see Hist. Aiiitn. 

 i. 5. § 3 ; it takes its food on the land, (viii. 2. § 5.) Schneider {Ainwt. ail Hist. An. 

 i. .5.) thinks Aristotle alludes to some genus of amj>hibia allied to the Siren lacer- 

 Una, Lin., the mud eel of the U. S. of America, or to the Proteus angninus. Cuvier 

 seems to have entertained the same opinion ; it must be confessed, however, that 

 there are difficulties in the way of this explanation, for all the i?/rc««/<f are possessed 

 of lungs as well as gills dui-ing the whole period of their existence. It is possible 

 that the animal to which the Cordylus bears the closest resemblance, though the points 

 of agreement are not altogether satisfactory, is a young specimen of eft, ( Suluman- 

 driilcE) at the period of its life when the branchiiK and feet are developed, and \\hilc 

 the lungs are in a rudimentaiy state, so that they might have been overlooked. Still 

 there is even, in this case, the following difficulty to get over, viz., that, according to 

 our author, the Corch/lns takes its food on the land, while the young eft, at the 

 above-named period of its existence, is aqimtic in its mode of life ; but it is possible 

 Aristotle may have observed young efts to crawl upon the ground before the 

 entii'e absorption of thebranchiii\ when the pulmonarj' apparatus was sufficiently ad- 

 vanced to enable them to exist out of the water, and that from lack of following up 

 his dissections at ditiercnt periods of its existence he has erroneouslj- supposed that 

 the young eft, with a temporary possession of branchiiu and a temporary absence of 

 lungs, was an adult form, percnni-ln-anchiate and always destitute of lungs. Ilon- 

 delet has tigured a monstrous form, which he calls Cordylus, to which the reader 

 who is fond of the curious may refer. {Hist, des l'oiss.\). 176.) Schneider refers 

 to a long disputation by J. Hermann [Cumment. ad Tabulam. cjjinlt. f. 294.) to 

 which we have not had opportunity of access. 



J Comp. also Z't'7^(v<.;;iyY.7/o//f, ix. 29, ed. Bekker. " That insects do not respire 

 has been remarked by us before ; this is evident in small animals, as flies and bees, 

 for they can swim a long time if the water be not very hot or very cold." The 

 beautiful mechanism of the tracheal apparatus whereby insects respire was, of course, 

 unknown to Aristotle, who had no microscope. He Avas aware, however, of the fact 

 tliat if an insect were covered with oil it would speedily die {Hist. A/iim. viii. 2G) ; 

 see also Phny, N. H. xi. 19, Aelian Hist. An. iv. 18 ; Basil (a.d. 329) seems to 

 have been aware that insects admitted air through some external openings. He 

 says that if vinegar is si>read over insects that have been in oil they immediately 

 revive, the passages being thereby opened. {Homil. 8 in Hexcem.^ 



