ICHTHYOSAUR × ¹/₁₂₀ MOSASAUR × ¹/₆₀ PLESIOSAUR × ¹/₆₀

Plate 42

CROCODILE-LIKE REPTILE
× ¹/₅₀
PHYTOSAUR

FLYING DINOSAURS

RHAMPHORHYNCHUS × ⅙ PTERANODON × ¹/₄₀

Ichthyosaurs.—

These were extinct, short-necked, marine reptiles that were fish-like in appearance. Ichthyosaurs resemble the modern dolphins, and some of them attained lengths of 25 to 40 feet ([Pl. 41]), though the average was much less. The group is known from rocks ranging from middle [Triassic] to late [Cretaceous] in age.

Mosasaurs.—