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Description of a Sea Star {Crihellites Carhonarius) from 

 the Mountain Limestone of Northumberland, with a notice 

 of its association with Carboniferous Plants. By George 

 Tate, F.G.S., &c. 



Many crinoids of the class Ecliinodermata occur in the 

 mountain limestone formation ; and of Echinidse, belonging 

 to the same class, I have found two species in this formation 

 in Northumberland — Archseocidaris Urii (Flem sp) and 

 Archseocidaris Nerei, the former in the middle limestone beds 

 at Howick and Redesdale, and the latter in one of lower 

 limestones at Rugley, near Alnwick. But no species of 

 Asteroidea has as yet been recorded from this formation, 

 either in Northumberland or elsewhere. Recently, however, 

 I recognised one of this family in a block taken, Mr William 

 Wilson informed me, from the first sandstone above the Shil- 

 bottle coal. The specimen is an impression of the upper sur- 

 face only of the organism ; and although imperfect, yet, being 

 doubtless a sea star, and the first discovered in the formation, 

 it deserves the attention of Palaeontologists. Without the 

 under surface, generic characters cannot be determined ; but 

 as the fossil has a considerable resemblance to the genus 

 Cribella, I have provisionally named it Cribellites Car- 



BONARIUS. 



The following characters can be observed : — Rays five, 

 rounded, lanceolate, five times as long as the disc, ridged in 

 the centre, covered with regular longitudinal rows of reticu- 

 lating tubercles ; disc small and tuberculated. The disc is 

 only "3 of an inch in diameter, while the rays are 1*5 inch in 

 length. There seems to be a circular depression near the 

 centre of the disc, which may be the impression of the madre- 

 poriform nucleus ; it has a faint resemblance to the impres- 

 sion of a crinoidal stem ; and if this were the case, it would 

 lend support to the view, that the nucleus in sea stars is the 

 analogue of the column of the Encrinite. In the form of the 

 asteroid, and in the characters observable, it is similar to 

 Cribella rosea, Muller ; but the disc of our fossil is smaller, 

 the rays proportionally longer, and the tubercles much nearer 

 to each other. The yellow micaceous sandstone, from which 

 this asteroid was obtained, is about 20 feet above the Shil- 

 bottle Coal, and about 10 feet below the " Eighteen foot 

 Limestone," which is the fifth limestone sill in the mountain 

 limestone of Northumberland ; it lies, I estimate, about 600 

 feet below the base of the millstone grit ; and as the forma- 



