’ DESCRIPTIVE REMARKS. ]xxix 
a di 
: ze FI = 5 2 
8 38 i oS ‘Ss 5 
Classes. “7 anita a = == = 
= asl b 3 Sh a lowe 
i Os a Ne rot PP Le 
wR ~ B A a Bs 
Y | 
| 
Plante, . 4 ‘ “ ; z 10 12 4 2 308 20 
Amorphozoa, , & 2 ; 19 =F 9 ex: 5) 
Rhizopoda, : : é 3 ape “co, 3 6 
Ceelenterata, 5 : 4 Wno93 Aes) ee 1 119 5 
Echinodermata, . : : a, | 83 22 21 { 129 || 
Annelida, . é : : eee a 1 2 19 er") 
Crustacea, . E C 3 : 267 21 13 Boa 59 20=— | 
Insecta, ‘ é 5 6 ‘ wee a ae me BY o- | 
Polyzoa, : : : 2 i a9 Le eS 6 55 BP 
Brachiopoda, : - c : 208 eee 99 15 157 20 
Lamelli- (| Monomyaria, 2 30 ar 22 3 140 6 
branchiata, { Dimyaria,  . 4 99 1 36 6 194 | 20 
Gasteropoda, : C c 5 96 ae 46 7 174 25 
Nucleobranchiata, ; 4 : ye alae 9 3 29 1 
Pteropoda, . A - 5 es Xi | Asay 4: 1 aes Des ht 
Cephalopoda, 2 . 2 3 77 = 52 9 145 2 
ict ied ae 7 ise, 8 BBN he) 21 
Reptilia, . A oy ot pee ee sok Palhn ce i Tol) «id 
1,154 149 | 383 56 1,741 167 
Having now passed briefly in review the assemblage of Animals 
and Plants characterizing the several groups of the great Paleozoic 
division (the most ancient in the stratigraphical series), in ascending 
order, it may now be useful to give here a shorter summary. 
Commencing with the oldest Fossiliferous rocks (at least in Britain), 
the Camsrian formation. In this series of strata organic remains are 
few, marine worm tracks, and supposed Hydrozoan animals, plant-like 
in form, being the chief fossils. 
The more interesting and largely developed Siturtan rocks con- 
tain an abundance of certain classes of fossil animals; the most pro- 
minent being Graptolites, now generally believed to belong to Hydrozoa 
rather than Polyzoa; the extinct order of Zrilobites with other forms 
of Crustacea; Mollusca of several classes, that of Brachiopoda being 
most prevalent; Corals of a peculiar type and Crinoids are also abund- 
ant in the Upper Silurian; and the first evidence, although but slightly, 
of Vertebrata, in the presence of Ganord fish, is obtained from the very 
uppermost beds. 
We next arrived at the consideration of the Orp Rep Sanpstone 
and Drvontan series of rocks. In the first named of these the remains 
of Fish (probably fresh water forms), are abundant, and almost the only 
fossils; Ganoids being the most prevalent, with a few Placoids. The 
* At least twelve species of Labyrinthodont Amphibia (Reptilia) are now known 
from Coal Strata, eight of them having been found at Jarrow Colliery, county Kilkenny 
(See Descriptive Remarks, avte p. 1xxiy-y.). W. H. B. 
