144 How is the Camhrian divided? — Matthew. 
The third fauna (Lower Lingula flags) has the following 
genera : 
Olenus. *Euloma. 
^ Faraholina. * Agnostus. 
Of these three extend upward to the higher zone, leaving 
only Olenus as peculiar to this fauna. 
In the fourth fauna (Dolgelly group) are the following 
genera : 
^Eidoma. Peltura. 
^Farabolina. Sphc&wphthalmus . 
*Paraholinella- (?) Gtenopi/ge. 
* Conocephalites. *Agnostus- 
Five of these genera extend upward into the next zone. The 
Conocephalites have been called Dicellocep)hali, but they are 
not the typical forms with spined pygidium, which occur 
higher; they are related to Conoceijhalites (sens, strict) and 
Conocephalina,\ -which has short spines found by Brogger in 
the Paradoxides zone. The genus is not reported from the equiv- 
alent beds in Sweden, where the genera of the second column 
held possession, but it is found in the fauna of Hof in Bavaria. 
The fifth Cambrian fauna (Tremadoc group) exhibits the 
following genera. 
Psilocephalus. °Eulo7na. 
Asaphus. °Faraholina {!) 
Cheirurus. ° Paraholinella ( ?) 
° Angelina. ° Dicelloceph alus. 
Nesuretus. Gonophrys. 
Niohe. Ampyx. 
Ogygia. ° Agnostus. 
Dionide. 
In this assemblage of fourteen genera only six represent 
"Cambrian forms" of trilobites, but in the first column are a 
number of genera which, once thought to have appeared first 
at this period, are now found to be present in the West of 
America by representative forms at a lower horizon. Hence 
these, although hitherto regarded as Ordovician, as already 
remarked, are essentially Cambrian types. 
It will be observed that in the Welsh area the four Cambrian 
faunas, which have trilobites, show a correspondence of genera 
■1-Om paradoxidesskifrene ved Krekling. 
