Science. 1972 Jul 28;177(4046):354-6. doi: 10.1126/science.177.4046.354.
Spongy mesophyll tissue has been discovered preserved in fossil leaf compressions. The fossils occur in an outcrop at Genesee, Alberta, Canada. The fossiliferous beds belong to the Edmonton formation of Upper Cretaceous-lower Tertiary age. The mesophyll characteristic, when taken in conjunction with other characteristics, was found useful in the identification of some fossil leaves. Numerous detailed observations as well as comparisons of both living and fossil leaves show that the remains represent neither the epidermal nor the palisade tissue.
海绵状叶肉组织已在化石叶标本中被发现保存下来。这些化石出现在加拿大阿尔伯塔省 Genesee 的一个露头处。含化石的地层属于上白垩统至下第三系的 Edmonton 组。当与其他特征结合使用时，这种叶肉特征在鉴定一些化石叶方面非常有用。大量详细的观察以及对活叶和化石叶的比较表明，这些残留物既不是表皮组织也不是栅栏组织。
