102 
THE GEOLOGICAL MIDDLE AGE. 
Of all these strange old forms, so singularly 
uniting features of Fishes and Reptiles, none has 
given rise to more discusion than the Pterodacty- 
lus, (Figure 8,) another of the Saurian tribe, 
Fig. 3. 
associated, however, with Birds by some natural- 
ists, on account of its large wing-like appendages. 
From the extraordinary length of its anterioi 
limbs, they have generally been described as 
wings, and the animal is usually represented as 
