PLATE III. 



Calamodendron commune. 



Fig. 1. Specimen No. 3, from the " Hard Seam" of Coal at South Owram, near 

 Hahfax ; showing- the outside of a decorticated plant, of small size, with ribs^ furrows, 

 and a joint. Magnified 2 diameters. 



Fig. 2. Transverse section of the same specimen, showing the wedge-shaped 

 bundles of pseudo- vascular tissue, originating from " orifices" and parted by lax tissue. 

 The central axis has for the most part disappeared. Magnified 10 diameters. 



Fig. 3. A longitudinal section of the same stem, showing one of the horizontal 

 diaphragms. Magnified 7 diameters. 



Fig. 4. A tangential section of the same specimen, showing three oval-shaped 

 bundles of vessels found at the joint, as well as some elongated oval masses of 

 cellular tissue, not unlike medullary bundles. Magnified 12 diameters. 



Fig. 5. A longitudinal section of a portion of the same specim.en, showing the 

 oval openings on the walls of the tubes forming the pseudo-vascular cylinder. 

 Magnified 50 diameters. 



"o" 



Fig. 6. A tangential section of the same specimen, showing one of the 

 medullary (?) bundles. Magnified 45 diameters. 



Fig. 7. Transverse section of a very young stem (Specimen No. 4), slightly 

 compressed, showing the structure of the central axis, the wedge-shaped bundles of 

 pseudo-vascular tissue originating from "orifices," and parted by coarse tissue. 

 From the Upper Brooksbottom Seam of Coal. Magnified 34 diameters. 



