STKUCTURE OF LEPIDOSTROBUS. 37.") 



Lepidostrobus FOLiACErs, sp. nov. 



Lepidostrobus, sp., Will., ^ Oro;anization of the Fossil Plants of the Coal Measures/' Part XIX., Tliil. 

 Trans. 1893, p. 27, fig. 57. 



Cone small, about 1 centim. in diameter. 



Sporopliylls (pedicels) leaving the axis at an oblique angle ; directed upward. 



Pedicel (as seen in transverse section) with two " pads " of sclerenchyma serving as 

 lateral supports for the sporangium. 



Pedicel with a longitudinal ridge on its upper surface, appearing, in transverse sections 

 of the pedicel, as a distinct stalk to the sporangium. 



Laniinie of sporophylls composed of a large-celled parenchyma, many of the cells 

 showing dark contents (" secretory sacs "). 



The researches above detailed have been carried on at the Natural History Museum 

 while holding the Marsliall Scholarship at the Royal College of Science, London. I am 

 greatly indebted to Dr. D. H. Scott, M.A., F.R.S., for much valuable help and criticism, 

 and to Dr. H. Woodward, LL.D., F.R.S., and Mr. R. B. Newton, F.G.S., for facilities 

 to study and photograph the specimens in their charge at the Museum. 



EXPLANATION OF THE PLATES. 

 Plate XXXVI. 



Lepidostrobus oldhatnius {a). 



Fig. 1. Part of transvci-se section of whole cone, m., pith-cavity; x.. xylem of axis; i.s., inner s})aec 

 with leaf-trace bundles ; i.e., inner cortex with leaf-trace bundles passing through it ; 

 m.c, middle cortical space; l.t., leaf-trace bundles; o.c, outer cortex; Pa., pariclinos; 

 sph., sections of sporophylls ; sm., sporangia and spores. S. 85. X 6"5 



Fig. 2. Transverse section showing vascular cylinder, inner cortex, and emerging leaf-trace hunrlU-s. 

 X., elements of the xylem ; p., parenchymatous elements surrounding the xylem cylinder, witli 

 short trachcides (" harred cells ") at s.t. ; l.t., leaf -trace bundles in inner space ; i.e., inner 

 cortex with leaf-trace bundles passing through it; m.c, middle cortical space; /..?., inner 

 space. C.N. 1613 d. x about 150. 



Fig. 3. Longitudinal section of the central cylinder. (The section is not radial, and so does not 

 penetrate the pith-cavity.) a^., xylem ; p., investing parenchyma with short tracheides 

 at the periphery of the xylem cylinder. C.N. 1613. x about 160. 



Fig. 4. Two of the short tracheides from C.N. 1613. x 210. 



Fig. 5. Longitudinal section passing tangentially through the smaller peripheral elements of the xylem. 

 (From a photograph.) a., vascular axis surrounded by parenchyma p. : /./'., k'af-rr;tcr 

 enclosed in the parenchymatous investment of the vascular cylinder; / /"., leaf-trace in inner 

 space; l.t'"., leaf-trace in outer space (middle cortical space); i.e., inner cortex. C.lS. 1613. 

 X 54. 



Fig. 6. Tangential section through outer cortex, showing emerging sporophyll bundles. (From a 

 photograph.) Pa., parichnos. C.N. 572. X about 20. 



Fig. 7. Part of radial section showing the proximal end of a sporophyll and its vascular bundle. (From 

 a photograph.) o.c, outer cortex of axis; sh. and sh'., sheath of cells continuous with those 



