22 
John, N. B. They were of low orders, chiefly mosses and ferns. 
Holoptychius, Glyptolepis, Diploptej'tis — fishes from the Old Red 
Sandstone of Scotland. These are nearly all Ganoids, as may be 
seen from the large, bony scales with which they are covered. 
Cyathophylliim, Cystiphylum. Zaphrentis — Cup corals. 
Case 3B. — Upper Devonian fossils. Large, polished masses 
of Acervuhiria from Iowa, a honey-comb coral. Dictyophyton — 
belongs to the class of sponges. Aspidosoma, Furcaster — Aster- 
oids. Spirifer, Orthis — Brachiopods. Goniatites — represents the 
Cephalopods. They are of the same type as Orthoceras^ but are 
coiled and the junction of the septa and shell (suture) is zigzag 
instead of straight. Bothriolepis — Ganoid fish. Note the thick, 
bony plates or armor. 
Floor Case B. — Fossils of the Hamilton Group (Devonian) 
from Hockberry Grove, Iowa beds and Millwaukee, Wisconsin 
beds. Collection of Carboniferous fossils from Mazon Creek, 111. 
Gift of J. C. Carr, Esq. 
Collection illustrating methods of petrifaction and preserva- 
tion of fossils. Here it will be seen that the common notion that 
animals and plants can petrify or turn to stone entire is quite 
erroneous. Fossils are chiefly of the nature of hard parts, such as 
bones or shells of animals, preserved, or are natural casts of their 
form. 
HALL 36. 
Cases 4 A, 4B, 4C, 4D and 5 A. — Fossils of the Carbonifer- 
ous Age, or age of coal plants. Naturally, land plants are the 
striking features of this age. They belong to five great families. 
Conifers, Ferns, Lepidodendrids, Sigillarids, and Calamites. 
Cordaites. This tree is allied to the Conifers, and had, proba- 
bly, a straight trunk 6o or 70 feet in height. Trigonocarpum^ in the 
same case, is supposed to represent its fruit. Ferns are repre- 
sented by Pecopteris, Neuropteris and others, many imprints of 
sections of the fronds being shown. These frequently form the 
center of clay concretions, as may be seen in some which have been 
broken open. Sections of trunks of Lepidodendrids and Sigilla- 
rids. One of the latter shows by its size that the trunk of the 
original tree must have been many feet in diameter, and perhaps 8o* 
