SILURIAN RADIATA. 161 



Strephodes vermiculoides (M'Coy). 



Sp, Char. Corallum of closely grouped, round columns of ex- 

 ceedingly irregular diameter from frequent intermittence of 

 growth, producing very unequal annular swellings and fun- 

 nel-shaped rings j external wall thin, marked by lamellar sulci 

 (six in 3 lines at a diameter of 1 inch, or about twenty all 

 round, indistinct at the more usual diameter of 8 or 9 lines) ; 

 cup deep, lined with alternating large and smaller vertical 

 lamellse irregularly uniting about the centre, their edges and 

 sides papillose and perforated, the union of which papillae forms 

 a dense broad granular margin to the cup obscuring the la- 

 mellae : horizontal section, about twenty slightly and irregu- 

 larly curved, flexuous, radiating lamellse, extremely thin, indi- 

 stinct and equal in the dense, nearly solid or granular outer 

 area, where they are connected by very close, minute, curved, 

 vesicular plates ; one half of the lamellse scarcely extend beyond 

 the outer zone, the other half suddenly increase in thickness 

 and proceed towards the centre, where they are irregularly 

 united, connected by few large, curved, vesicular plates, form- 

 ing nearly transverse rows of irregular cells : vertical section, 

 outer third on each side very dense, of extremely small rounded 

 vesicular plates nearly united, inner half of diameter composed 

 of much larger^ thin, irregular vesicular plates. 



This coral may be distinguished from the Cystiphyllum cylin- 

 dricum (Lonsd.) by the distinct radiating lamellse towards the 

 centre, and the small size of the vesicular structure towards the 

 circumference, forming an almost solid white granular structure. 

 The Devonian Cyathophyllum vermiculare of Goldfuss (also a 

 Strephodes) is almost identical in external appearance, but has 

 the radiating lamellse thickest in the outer area, straighter and 

 alternately of very unequal thickness, and wants the remarkable 

 dense, almost unradiated outer zone. The lamellse as usual are 

 less numerous in young tubes of smaller diameter. 



As far as I can judge from the figure alone, I should think the 

 coral figured by Lonsdale as the Cyathophyllum ccespitosum of 

 Goldfuss (S. S. t. 16. f. 10) from the Wenlock rocks might be 

 probably referred to this species, which, in general size, forrn and 

 mode of grouping of the branches, it resembles ; it is quite cer- 

 tain that it has no relation to the true Eifel species of Goldfuss, 

 which is common in the Devonian limestone of Newton Bushel, 

 Torquay, Plymouth, &c., which has slender, even, dichotomous 

 branches and broad transverse diaphragms, &c. 



Wenlock limestone of Wenlock and near Aymestry. 



[Col. University of Cambridge.) 



