The scaly skin of the reptile, compared with the moist skin of the amphibian, is the most basic and obvious difference between these two classes of animals.
(The scaly skin of the reptile, compared with the moist skin of the amphibian; is; the most basic and obvious difference between these two classes of animals)
The scaly skin of the reptile, compared with the moist skin of the amphibian
is
the most basic and obvious difference between these two classes of animals