STEUCTUEE OF LEPIDOSTEOBUS. 359 



is about 9*5 centims. A third section (C.N. 1776 c), obtained from the Bullion Eed at 

 Oldham, agrees so exactly with C.N. 1776 a and 1776 b as to leave no question as to 

 its being the same form. 



Comparison of these three slides (C.N. 1776 a, 1776 b, 1776 c), Avhich I may for 

 convenience designate " Wild's Cone," with the type slides of Lepidostrobus oldhamius, 

 Will. (C.N. 568, 574), shows that, so far as the corresponding structures can be compared 

 in the absence of a transverse section of Wild's Cone, they are identical. It seems 

 possible therefore, with the aid of these beautifully preserved longitudinal sections, to 

 work out the structure of the cone in this type in greater detail than has hitherto been 

 done. 



In Williamson's " Organization," &c.. Part XIX. 1893, fig. 57, is figured a LepidO' 

 atrobus which seems to merit more notice than that accorded in the text : " Fig. 57 is a 

 fine longitudinal section of 2^, Lepidostrobus (x 4, C.N. 1614) with radially elongated 

 sporangia and sporangiophores. It is homosporous " (p. 27). Although the sections in the 

 Williamson Collection, with others lent by Dr. Scott, do not enable me to give anything 

 like a complete account of the strobilus, yet they are sufficient to show that it is a 

 distinct form, and for this type I propose the name of Lepidostrobus foliage us, on 

 account of the leaf-like character of the sporophyll-laminae. 



Most of the other slides in the Williamson Collection appear to agree more closely 

 with the original sections described by Williamson Oi^ Lepidostrobus oldhamius,8Liid under 

 this type name I shall describe some of them in this paper. There are, however, minor 

 differences in structure in the different sections, some of which, when more or better 

 material comes to be examined, may ultimately prove to be of specific value. At present 

 the difficulty (in dealing with isolated sections such as these) of making certain whether 

 the differences are really of specific value, or are only variations dependent on the age, 

 the degree of development, or the part of the cone from which the section was cut, is 

 very great. It seems safer therefore, at present, to adopt the name L. oldhamias for a 

 type of structure of which some of the most marked variations will be described in the 

 following paper as L. oldhamius (a), (/3), and (7). 



Before proceeding to the detailed consideration of the slides specially to be considered 

 in this communication, a resu7rie may be given of our knowledge of Lepidostrobus, 

 particularly of the L. oldhamius of Williamson. The generic characters given by 

 M. Zeiller * may be accepted as the modern conception of the genus. The following 

 literal translation I take from Dr. Scott's memoir on Spencerites f, the italics being 

 M. Zeiller's own : — " Cones offructljication cylindrical, oblong, or ovoid ; composed of a 

 woody axis bearing sporangiferous bracts arranged in a spiral, and somewhat crowded. 

 Bracts formed of a narrow pedicel, usually normal to the axis, and of a uninervate 

 limb, lanceolate or linear-lanceolate in outline, generally erect, and often even applied 

 to the surface of the cone. Sporangia ovoid, solitary, fixed upon the superior face of the 

 pedicel of the bracts." 



• ' Bassin Houiller de Valenciennea. Description de la Flore Fossile," 1888, p. 4<J6. 

 t PhU. Trans, B. 1898, p. 99.] 



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