22 
from the fishes of the present day, however. The Ganoids were 
covered with thin, bony scales, had teeth of reptilian character 
and jointed, paired fins. The Placoids had cartilaginous skele- 
tons, no scales, no gill covers, and many of their characters were 
embryonic. 
Lower Devonian fossils of the Corniferous period. Favos- 
ites — Honey-comb corals. Heliophyllum — Cup corals. 
Ophiura, Loriolaster — Asteroids similar to modern starfishes. 
Being free-moving Echinoderms, they mark the introduction of 
a higher type than the attached Crinoids. Macropetalichthys — a 
Ganoid fish. 
Lower Devonian fossils. Syringopora — Chain corals. Zaph- 
rentis — common and characteristic cup corals. Orthis, Atrypa^ 
Spirifer — Brachiopods. Coccosteus — a typical Ganoid from the 
Old Red Sandstone of Scotland. 
Middle Devonian fossils. Psilophyton, Sphenopteris, etc. — 
early land plants from the Devonian beds of St. John, N. B. 
They were of low orders, chiefly mosses and ferns. Holoptychi- 
us, Glyptolepis, Diplopterus — 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. CyathophyP 
lum, Cystiphyllum, Zaphrentis — Cup corals. 
Upper Devonian fossils. Large, polished masses of Acer- 
vularia from Iowa, a honey-comb coral. Dictyophyton — belongs 
to the ' class of sponges. Aspidosoma, Furcaster — Asteroids. 
Spirifer, Orthis — Brachiopods. Goniatites — represents the Cepha- 
lopods. It is of the same type as OrthoceTas, but 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. 
Fossils of the Carboniferous Age, or age of coal plants. 
Naturally, land plants are the striking features of this age. They 
belonged to five great families. Conifers, Ferns, Lepidodend- 
rids, Sigillarids, and Calamites. 
Cordaites, This tree is allied to the Conifers, and had, prob- 
ably, a straight trunk 60 or 70 feet in height. Trigonocarpum, in 
the same case, is supposed to represent its fruit. Ferns are rep- 
resented by Pecopteris, Neuropteris and others, many imprints of 
sections of the fronds being shown. These frequently form the 
