23 
to loo feet high. Stigmaria, probably represent the under-water 
stems of the Sigillarids. 
The animal life of this period is characterized by the abun- 
dance of Crinoids. These reached their highest devevelopment 
at this time. Many specimens are shown in this case, including 
Platycrinus, Scaphycrinus and Pentremities, the latter a Blastid 
or bud crinoid. Corals were also abundant, as represented by the 
columnar Lithostrotion,2. true polyp coral, Dibmiophyllum, a 
cup coral. The cork-screw-like Bryozoan Archimedes is illus- 
trated by several specimens. Spirifer and Productus are the 
leading genera among the Brachiopods. The Gasteropods, uni- 
valve mollusks, are represented by Bellerophon and Pleurotom- 
aria, Melonites, in the upper part of Case 4, was an Echinoid 
allied to the sea-urchin of the present day ; it differs from the lat- 
ter, however, in having large plates and small spines. A cast on 
the. wall shows the foot-prints of one of the first reptiles, Sauropus. 
It was a four-footed, crawling animal, with thick, fleshy feet about 
four inches long. 
Case 5 A, Hall 59. — Permian, or closing age of the Carbonif- 
erous. Fishes are represented by the Palceoniscus. Reptiles by 
the A rchegosaurus, an animal which combined the characters of 
reptile and fish, having both lungs and gills, and being covered 
with scales. Plants are represented by leaves of the Walchia, a 
Lycopod. 
South and West Walls of Hall 36.^ — Large slabs and casts 
showing tracks of reptiles of the Triassic period. Little is known 
about these animals, except so much as can be learned from their 
foot-prints. The Brontozoum was a three-toed animal, probably 
at least 14 feet in height, with a stride of over 3 feet. Cheiro- 
therium (South Wall, Hall 59, ) was so named from the resemblance 
of the foot-print to the human hand. It was a four or five-toed 
reptile, probably of the order of the Labyrinthodonts. A cast 
showing the shape of the skull of the latter animal may be seen 
at the right. 
Cases 5, 6, 7, part of 8 and Walls of Hall59.-Fossilsof Meso- 
zoic time, the age of reptiles. This age is characterized by the 
number and size of its reptiles, especially Amphibians. Here, too, 
are introduced the first mammals, birds and fishes of the modern 
type, and among plants the angiosperms. 
