FOSSIL CORALS. 89 



genus. Carboniferous limestone rock is frequently 

 composed of its dense clusters of corallites, in masses, 

 looking like so many bunches of twigs. Lithostro- 

 tion jtuiceum is perhaps the commonest species. In 

 Derbyshire Lithostrotion arachnoideum forms large 

 masses of the limestone. When these corals weather 

 out, they stand in relief on the stones, as if the latter 

 were covered with dead ivy twigs. 



The Carboniferous limestone rising behind the 

 pleasantly situated town of Kendal, in Westmoreland, 

 is rich in corals, Cyathaxinia being more abundant 

 there than in any other English locality I know of. 

 For immense variety of corals, however (associated 

 with other fossils), and for the chance of picking up 

 some good, rare, and, it may be, neiv things, commend 

 me to the little quarry which has long been worked 

 in the outlier of Carboniferous limestone at Hafod, 

 about two miles from Corwen, in North Wales. The 

 tourist will easily find it by taking the pretty foot- 

 path by the River Dee — just here almost at its best 

 as regards lovely scenery. Having found the quarry, 

 he will be safe for a few hours at the least. There 

 is an abundance of the elegant coral Phillipsastrea. 

 If the student's eyes are open, he may read off the 

 story of that ancient coral-reef and its fauna without 

 much fear of drawing false inferences. 



Clitheroe is good for all the fossils of the forma- 

 tion I am speaking of; and at Bolland — about four 

 or five miles off, in a very lovely and richly wooded 



