金剛經纂要刊定記 4.25

4.25

畜具四者。《正法念經》云：「化生金翅鳥，能食四生龍，乃至濕生也。」然禽獸雖殊，皆畜生道攝，餘獸皆胎，餘鳥皆卵也。

Regarding "animals possessing all four": the Saddharmasmṛtyupasthāna Sūtra says: "Transformationally born garuḍas are able to eat the four kinds of born nāgas, up to moisture-born." However, although birds and beasts are distinct, all are subsumed under the animal destiny; the remaining beasts are all womb-born, and the remaining birds are all egg-born.