PalcEOZoic Corals and For aminif era. 15 



writer. I am unable to afford any information on what would 

 under the circumstances be the most interesting point, namely 

 the mode of production of new columns : taking all the circum- 

 stances into consideration, I suspect the mode of increase was 

 similar to that I have described in Lonsdaleia generally, the ex- 

 ternal prismatic form (which is of itself of no value) being pro- 

 duced by the pressure of a closer mode of growth than in the 

 L. duplicata. As it is impossible to conceive a Strombodes (or 

 Lithostrotion) splitting into easily-separable columns, I provi- 

 sionally therefore place it in Lonsdaleia. 



Rare in the carboniferous limestone of Kendal. 



{Col. University of Cambridge.) 



Nemaphyllum (M'Coy), n. g. 

 Gen. Char. Corallum composed of numerous inseparably united, 

 polygonal, prismatic tubes, each having a straight, thin, flat, 

 fillet-like solid, or nearly solid, 

 axis, from which, in the hori- 

 zontal section^ the fine nume- 

 rous radiating lamellae are seen 

 extending directly to the walls ; 

 radiating lamellae connected by 

 very fine transverse dissepi- 

 ments only visible externally in 

 the outer area : vertical section 



shows three distinct areas ; ^;.^<^^-.^.^^L~,^^;*f-.*> ^--^^^>;;. 

 1st, the thin flat axis; 2nd, a ^S^^^^ 

 sharply deiined cylmder oi very ^^*^r#|p^^I?^5ft 



5&m> 



minutely vesicular arched plates, 



the rows directed from the axis Section and terminal stars of Ne- 



obhquely downwards and out- f «f%^[^^« = « «• axes; 6. young 

 1 •'■•T .-,• . ,, n ^ bud withm the ai'ea 01 the parent, 

 wards ; outside this is the ord ^ 



area of similar small arched plates forming a minutely vesi- 

 cular structure slightly smaller than that of the inner zone, 

 but the rows directed obliquely upwards and outwards : repro- 

 duction by small circular buds developed within the area of the 

 parent star. 



In mode of reproduction and tri-areal structure this genus ap- 

 proaches Strombodes (as above understood), from which it differs 

 altogether in the nature of the axis, which in all the species of 

 that genus is cylindrical, composed of numerous plates variously 

 twisted together, and giving a cellulose section in every direction ; 

 the axis of the present group on the contrary forms a thin, flat, 

 simply solid lamina, and is exhibited in a vertical fracture either 

 as a narrow opake white line, or as a broad ribbon-like fillet, ac- 

 cording to whether the section is in the direction of its width or 



