GENERATION OF ANIMALS, II. i. 



feet state, as the Fishes, and the Crustacea and the 

 Cephalopods as they are called, whose eggs do grow 

 in size after they are laid.^ 



All animals that are viviparous [or o\'iparous] are 

 blooded, and animals that are blooded are either 

 \'i\iparous or o\'iparous, apart from those which are 

 completely infertile. Of bloodless animals. Insects 

 produce a larva ; this holds good both for those which 

 are formed as a result of copulation and those which 

 themselves copulate. ** (A note of explanation : there 

 are certain Insects which, although formed by spon- 

 taneous generation, nevertheless are male and female, 

 and as a result of their copulation something is formed, 

 though it is imperfect : the cause of this has already 

 been stated elsewhere.) 



Actually there is a good deal of overlapping be- ciassifica- 

 tween the various classes. Bipeds are not all \-i\d- a'^^ais. 

 parous (birds are o\'iparous) nor all oviparous (man is 

 viviparous) ; quadrupeds are not all oviparous (the 

 horse and ox and heaps of others are \i\iparous), nor 

 all viviparous (lizards and crocodiles and many others 

 are oviparous). Nor does the difference lie even in 

 having or not having feet : some footless animals are 

 viviparous (as vipers, and the Selachia), some are 

 oviparous (as the class of fishes, and the rest of the 

 serpents) ; and of the footed animals many are ovi- 

 parous, many viviparous {e.g., the quadrupeds already 

 mentioned). There are footed animals which are 

 internally viviparous (as man), and footless ones also 

 (as the whale and dolphin). So we find no means here 

 for making a division " : the cause of this difference 



and my note there), as used, though for a different purpose, 

 by Plato in Sophist and PoUticus {e.g., the division into to 

 ne^ov and to vevarucov at Sophist 220 a). 



137 



