80 
PROFESSOR W. C. WILLIAMSON ON THE ORGANIZATION 
PLATE VI. 
Eig. 33. External aspect of the upper part of a small strobilus of Calamostachys Binneyana 
from Oldham, enlarged 6 diameters. 
Eig. 34. Transverse section of part of a sterile foliar disk of Calamostachys Binneyana , 
magnified 24 diameters. 
Eig. 35. Part of the periphery of a similar section to fig. 34. 
Eig. 36. Transverse section of Calamostachys Binneyana made in the plane of a verticil 
of sporangiophores, magnified 27 diameters. 
Fig. 37. Transverse section of the same specimen as fig. 36, but made in the plane of 
an internode, intermediate between a fertile and a barren verticil, magnified 
12 diameters. 
Eig. 38. Central vascular axis of fig. 37, enlarged 80 diameters. 
Fig. 39. Part of the outer surface of a sporangium, magnified 98 diameters. 
PLATE VII. 
Eig. 40. Section of the wall of a sporangium of Calamostachys Binneyana made trans- 
versely to the longer axes of its cells, magnified 98 diameters. 
Fig. 41. Section of a cell of the wall of a sporangium of the same, made parallel with 
its longer axis, and showing one of its barred lateral walls, magnified 98 
diameters. 
Fig. 42. Inner surface of part of a sporangium-wall of the same, magnified 98 diameters. 
Eig. 43. Cluster of spores of C. Binneyana , showing the spores enclosed in mother- 
cells, magnified 140 diameters. 
Fig. 44. Fertile stem of an Asterophyllites , from Brooksbottom, from which strobili 
have been detached, enlarged 2 diameters. 
Eig. 45. “ Catamites ” verticillatus , reduced to two thirds of the natural size. 
Eig. 46. Transverse section of a young root with two clusters of rootlets of Asterophyl- 
lites, from near Oldham, magnified 12 diameters. 
PLATE VIII. 
Eig. 47. Part of the bark of fig. 46, enlarged 80 diameters. 
Eig. 48. Vertical section of part of the same root with one cluster of rootlets, enlarged 
18 diameters. 
Fig. 49. Portion of a similar section to fig. 48, showing the two layers of bark, 
enlarged 80 diameters. 
Fig. 50. Tangential section of the vascular axis of fig. 46, enlarged 75 diameters. 
Fig. 51. Part of a radial longitudinal section of the same vascular axis, made in the 
plane of a medullary ray, enlarged 100 diameters. 
lig. 52. Tangential section like fig. 50, but passing transversely through avascular 
bundle going to one of the clusters of rootlets, enlarged 75 diameters. 
