EXPLANATION OF PLATE 3. B. 



UPPER PALEOZOIC ZOOPHYTA. 



1 ASTR^A (PALASTR^A) CARBONARIA (M-'Coy). Terminal stars, natural size, from Derbyshire. 



2 NEMATOPHYLLUM CLISIOIDES (M^Coy). Natural size, shewing the form of the terminal stars, from 



Derbyshire. 



2 a Vertical section magnified three diameters, shewing the solid axis and the characters of the outer and inner 



areas, and giving the profile of the terminal star at top, shewing the narrow, steep, outer area, tlie wide tent- 

 shaped inner area, and the projecting axis. 



2 h Horizontal section of one star magnified three diameters, shewing the flat axis, the flexuous radiating lamella, 



and the few rows of vesicular plates of the outer area. 



3 NEMATOPHYLLUM MINUS (M-^Coy). Portion of large mass natural size, from Umestone of Kendal ; 



shewing the weathered terminal stars (a pecuharity of weathering shewing the solid walls and axes as impressed 

 lines), the very slight convexity of the inner and outer areas, and the occasional circular young buds developed in 

 the comers of some of the stars. 



3 a Vertical section magnified three diameters, shewing the character of the axis, and the vesicular plates of 



both areas, together with the supposed original form of the star deduced from the direction of the vesicular 

 plates of both areas. 



3 h Horizontal section magnified three diameters. 



4 STROMBODES CONAXIS (M'=Coy). Portion of larger mass natural size, from Derbyshire; shewing the 



appearance of the weathered terminal cups with the projecting conical axis. 



4 a Vertical section, the upper half polished, shewing the two rows of large cells of the outer area, the large, nearly 



horizontal cells of the inner area, and the fine, close, upward-curved lines representing the sections of the 

 conical plates of the axis, with the few irregular connecting filaments; the upper end gives a profile of the 

 terminal cup. The lower half is a rough section, shewing the separate cones of the axis entering into each 

 other. 



4 h Horizontal section shewing the axis, the lamelliferous cylinder bounded by a double circle of small vertical 



plates, and the large vesicular structure of the outer area. 



5 LONSDALEIA CRASSICONUS (M-^Coy). Natural size, from Arnside; shewing the rapid increase of tlie 



young. 



5 a Vertical section magnified three diameters, shewing the characters of the axis and the inner and outer areas, 



terminated by a horizontal section of half the tube shewing the relation of the characters exhibited in the two 

 sections. 



5 h Horizontal section magnified two diameters. 



6 LONSDALEIA RUGOSA (M'^Coy). Old branch, natural size, from Corwen ; shewing the concentric irregularities 



produced by the periodic death and continued growth of the main stem, and the mode of growth of the younf 

 slender stems. 



6 a Young perfect terminal cells, shewing the very prominent axis in the deep, sharp-edged cup. 



6 h Vertical section magnified three diameters, shewing the sohd line down the middle of the conical axis, the 



very oblique, close, cellular structure of the axis, graduating to the more open and less inclined cells of the 

 inner area; the divisional line and small rounded cells of the outer area; the top shews a profile of the ter- 

 minal cup, and the extension of the lamellEe, with their connecting plates. 



