49 
Here is the interesting Silurian bag-shaped Sponge, Case 116. 
Ischadites. Silurian Corals are well represented, 
as Cyathophyllum, Cystiphyllum, Lindstroemia, 
Omphyma, Acervularia, Favosites, Halysites, 
and others. The Stomatoporoids exhibit various 
modes of growth : Labechia, encrusting ; 
Strom atopora, boulder-like ; Clathrodictyon, 
tumulose. A fine collection of Graptolites, as 
Monograptus, Rastrites, and Diplograptus 
is placed here, chiefly from Bohemia ; whilst Stone- 
lilies are seen in the Wenlock forms, Periecho- 
crinus, Eucalyptocrinus, Taxocrinus, and others. 
The bud-shaped Cystoids, of Silurian age (Caryocrinus, Case 117. 
Pseudocrinites) are shown. Brittle-stars are seen 
in Protaster, Sturtzura, and Lapworthura ; 
whilst among Starfishes we may note Palaeocoma 
with its long brush-like series of ossicles, 
Bdellacoma and Rhopalocoma ; also Polychaete 
Worms (Cornulites) and Lamp-shells, as 
Strophonella, Chonetes, Orthis, Camaro- 
toechia, Spirifer, and many others. 
Continuing the Silurian series, Bivalved Molluscs are Case 118. 
seen in the cockle-like Panenka, the winged 
Pterinaea, and Prolucina. Of the Silurian 
Snails we may note Murchisonia, Euomphalus, 
Omphalotrochus, and the air-breathing 
Hercynella, also found in the Silurian rocks of 
Victoria. Cephalopods of this age are very striking 
in appearance and include Orthoceras, Geisono- 
ceras, Dawsonoceras, Kionoceras, and Ooceras. 
Trilobites are in great variety (Harpes, Illaenus, 
Goldius, Proetus, Acidaspis, Encrinurus, 
Calymene, and Cheirurus). Exceptionally large 
species of Ostracoda are seen here, in Leperditia 
from the Baltic clays, and there is also a fine head 
of a water-scorpion, Eurypterus. 
The oldest species of the Receptaculites group of Case 119. 
Sponges is shown here, in which the placing of 
spicules in quincuncial manner and the handsome 
platter-like form is very striking. Other Ordovician 
fossils are Corals (Streptelasma and Favosites) ; 
Graptolites (Didymograptus and Phyllograptus) ; 
