4 



BRITISH FOSSILS. 



The materials afforded by the specimens hitherto procured of Silurian 

 star-fishes are too imperfect to admit of more extended descriptions than 

 those here given. They are sufficient, however, to enable us to pro- 

 nounce with confidence on the tribe, and even genus, to which they have 

 belonged, and to assert, without hesitation, that the several species 

 described are distinct from one another. They are very interesting, 

 inasmuch as they exhibit the earliest forms of the order AsteriadcE. 

 Until within very few years past, it was supposed to have no palaeozoic 

 representatives ; instead of which we now find them in the oldest fossili- 

 ferous strata. On the Continent palaeozoic star-fishes have hitherto been 

 noticed only in France, and much higher in the series of rocks than those 

 now figured. In North America several forms have been found, appa- 

 rently nearly allied to our own, and in rocks of silurian age. The genus 

 to which I have referred these Silurian star-fishes is one of the most 

 cosmopolitan of all the groups of the order, having representatives at 

 present in arctic and antarctic, tropical and temperate, seas ; the indi- 

 viduals are perhaps most abundant in northern regions. Some of the 

 species have a considerable bathymetrical range. 



E. Forbes. 



April, 1849. 



