Palaozoic Corals and Foramikifera. 19 



the small flattened axis in the centre : horizontal section, divi- 

 sional lines of the stars thin, straight ; axis thin, half a line 

 wide; radiating lamellae thirty-six, thin, one half extending in 

 a flexuous manner from the walls to the centre, the inter- 

 vening ones also flexuous but of irregular lengths, most of 

 them reaching half-way ; transverse vesicular plates very few 

 and delicate, if visible at all ; vertical section, axis as in the 

 other species ; inner area very wide, of large, little-curved ve- 

 sicular plates, inclining obli({uely downwards and outwards; 

 one or two lengthened irregular cells reach from the axis to the 

 outer area ; outer area very narrow, of small, much-curved ve- 

 sicular plates inclining very obliquely upwards and outwards, 

 forming minute rounded cells about two in a row. 



This species much resembles some of the massive Astrseoid 

 Clisioj)hy(li(e of Dana by the conical tent- like aspect of the inner 

 area within the cups or weathered terminal cells; the distinct 

 flattened axis, resembling that of the other NemapliyUia^, will 

 however distinguish it. The flexuous character of the radiating 

 lamellse in the transverse polished section is remarkable. The 

 Astraa irregularis of Portlock's ' Report on Londonderry, ^& c 

 which I know to be a true Nemaphi/llum, resembles this species 

 in the small size of the stars and flexuous lamellje, but is easily 

 distinguished by the cells being simply cup-shnped, descending 

 uninterruptedly from the walls to the small, flat, prominent axis 

 iu the bottom of the cup, instead of the large tent-like boss 

 formed by the inner zone of the above. 



Forms irregular tuberose masses in the carboniferous limestone 

 of Derbyshire. 



[Col. University of Cambridge.) 



^ Nemaphyllum septosum (jM'Coy). 



Sp. Char. Corallum of long, insepai'able, slightly diverging five- 

 or six-angled tubes, witli an average diameter of 5 lines : ver- 

 tical section, axis straight, thin, flat, three-fourths of a line 

 wide; inner area composed of large, rather distant, slightly 

 ai'ched plates, each of which generally extends across the en- 

 tire area, so that one lengthened cell (rarely more) reaches 

 from one side to the other of this area, having the axis in the 

 middle ; outer area broad, of numerous minute, much-arched 

 vesicular plates inclining obliquely upwards and outwards, 

 about four of the little cells in the oblique line from the inner 

 area to the outer wall : transverse rough fracture showing the 

 inner area to be composed of slightly conical or cup-shaped 

 plates, their diameter equal to that of the area, and pierced in 

 the centre by the flat persistent axis : polished transverse sec- 



2* 



