PALJEOZOIC CONE-GENUS LEPIDOSTEOBUS. 215 



The cells, which compose the sterile ridge, are often somewhat elongated in a vertical 

 direction. The most interesting feature of the tissue is that, in some cases, the walls of 

 these elongated cells are marked hy delicate bars of thickening, indicating that they 

 were transfusion elements (PL 25. fig. 27). The distribution of these elements seems to 

 be very irregular. In certain tangential sections none can be detected (e. g.y the one 

 represented in PI. 25. fig. 26 a), in others there are a few, while in others again (e. g., 

 PI. 25. fig. 27), the tissue of the ridge appears to be almost entirely composed of such 

 elements, which are continuous below with the transfusion tracheides of the sporophyll 

 pedicel. 



The sporangia, as seen in tangential section, are much crushed and distorted, 

 dehiscence having already taken place. The structures inside the sporangium are 

 hence difficult to interpret, but there are indications of the existence of an outgrowth of 

 cellular tissue arising from the sterile ridge and penetrating into the cavity of the 

 sporangium [st.p., PL 25. fig. 27). 



The sporangium wall is of the usual columnar type (PL 25. figs. 20 a, 37, & 38), lined 

 internally by a narrow zone of delicate thin-walled tissue which is poorly preserved. 



(8) The Sjmres, 



The spores are somewhat more mature in Q. (5. than in Q. a. In the former cone they 

 are often still arranged in tetrads (PL 24. fig. 24). The ripe spores show the triradiate 

 marking with great distinctness, and the wall is also decorated with a narrow wing in 

 the equatorial plane (PL 24. fig. 25). Tlie greatest diameter of the spores is about 

 •03 mm , showing that the cone was either homosporous or microsporangiate. 



(9) Comparison icith other Species of Lepidostrobus. 



I 



The cone ol Lejndostrobus Mnnei/amts is considerably smaller in diameter than that of 

 the type form of L. oldhamius * or L. Bertrandi f. It also differs from L. oldhamius in 

 having no well-marked groove on the outer surface of the sporophyll lamina at its junction 

 with the heel %. The tangential width of the sporophyll trace, including its sheath, just 

 as it emerges from the inner cortex, is 0-15 mm. This is similar to the corresponding 

 diniension in the case of L. oldhamius, Will, (a) of Maslen §, but slightly less than that 

 of the type form of L, oldhamius ; in the case of one of the original sections of the 

 latter figured by Binney |1, I have found the sporophyll traces in this region to be about 

 0-25 mm. in diameter. Prom L. Bertrandi, L. Binneijanus also differs anatomically in 

 possessing a strongly thickened inner cortex, and in having delicate vertical striations 

 between the horizontal thickening bars of the scalariform tracheides (PL 24. fig. 18). 



The diameter of L. oldhamius, measured from sections 87 and 88, Binnej Collection, Sedgwick Museum, 



is about 3 cms. 

 t Th 



See Zalessty, M. ('08), p. 33. 



t Compare PI. 24. fig. 20 of the present paper with Seward, A. C. ('10), fig. 191 b, p. 188. Maslen's restoration 



form 



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