48 EXTINCT MONSTERS 
that on some slabs may be seen what is believed to be the 
impression of the tail of a Dinosaur as it dragged along over 
the moist sand of the seashore or estuary where these antediluvian 
creatures of old disported themselves (see Fig. 5). 
Those impressions which Hitchcock believed to have been 
made by birds show a regular increase in the number of joints 
) i ' 
TA 1 
fl in 
Fic. 5.—Footprints from the Connecticut Sandstone. The three tracks in the 
middle show the mark left by the tail, probably of a Dinosaur (After Hitchcock.) 
of the toes; the inner toe having two, the middle one three, 
and the outer one four joints. Now, it happens, by a remark- 
able coincidence, that in the case of birds the inner toes have 
three, the middle toes four, and the outer toes five joints, but 
the last two joints in each case make but one division of the 
track, so that their tracks correspond with those we are con- 
sidering. The discovery that some Dinosaurs have but three 
