er-plants of the bottom. The row
of short spoon-shaped stubby teeth around the front of the mouth would
serve to bite or pull off soft leaves and water-plants, but the animal
evidently could not masticate its food, and must have swallowed it
without chewing as do modern reptiles and birds.

"The brain-case occupies only a small part of the back of the skull,
so that the brain must have been small even for a reptile, and its
organization (as inferred from the form of the brain-case) indicates a
very low grade of intelligence. Much larger than the brain proper was
the spinal cord, especially in the region of the sacrum, controlling
most of the reflex and involuntary actions of the huge organism. Hence
we can best regard the Brontosaurus as a great, slow-moving animal
automaton, a vast storehouse of organized matter directed chiefly or
solely by instinct, and to a very limited degree, if at all, by
conscious intelligence. Its huge size and its imperfect organization,
compared with the great quadrupeds of today, rendered its movements
slow and clumsy; its small and low brain shows that it must have been
automatic, instinctive and unintelligent."

_Composition of the Brontosaurus Skeleton._ "The principal specimen,
No. 460, is from the Nine Mile Crossing of the Little Medicine Bow
River, Wyoming. It consists of the 5th, 6th, and 8th to 13th cervical
vertebrae, 1st to 9th dorsal and 3rd to 19th caudal vertebrae, all the
ribs, both coracoids, parts of sacrum and ilia, both ischia and pubes,
left femur and astragalus, and part of left fibula. The backbone and
most of the neck of this specimen were found articulated together in
the quarry, the ribs of one side in position, the remainder of the
bones scattered around them, and some of the tail bones weathered out
on the surface.

"From No. 222, found at Como Bluffs, Wyo., were supplied the right
scapula, 10th dorsal vertebra, and right femur and tibia.

"No. 339, from Bone-Cabin Quarry, Wyoming, supplied the 20th to 40th
caudal vertebrae, No. 592, from the same locality the metatarsals of
the right hind foot; and a few toe bones are supplied from other
specimens.

[Illustration: Fig. 23.--Skull of _Diplodocus_ from Bone-Cabin
Quarry, north of Medicine Bow, Wyoming.]

"The remainder of the skeleton is modelled in plaster, the scapula,
humerus, radius and ulna from the skeleton in the Yale Museum, the
rest principally from specimens in our own collections. The modelling