196 



STUDIES IN FOSSIL BOTANY 



name Cardiocarpon anomalum of Williamson * (not of 

 Carruthers). The seeds, which attained a great size, 

 became detached, together with the remains of the 

 sporophyll, and in this condition were never suspected 

 of belonging to a Lycopod until their origin had been 

 traced. The prothallus within the megaspore is not un- 

 commonly preserved 

 (see Figs. 81, 82), 

 and is found in the 

 younger stage, before 

 the integument has 

 grown up, as well as 

 in the mature ''seeds." 

 The tissue of the 

 prothallus may show a 

 considerable amount 

 of differentiation 

 (see Fig. 81); only 

 doubtful traces of 

 archegonia have so 

 far been observed. 

 In a microspore- 



u, base of sporangium ; mg, membrane of mega- bearinP" Strohilll^ 

 spore ; pr, prothallus. (G. T. G.) 



probably belonging to 

 Lepidocarpon Lomaxi, the microsporangia were also pro- 

 vided with integuments, less developed than those of 

 the megasporangiate cone. 



Lepidocarpon Lomaxi, and other undescribed species, 

 belong to the Lower Coal-measures ; the closely similar 



Fig. 82. — Lepidocarpon Lomaxi. Diagrammatic 

 section of "seed," tangential to cone. sp/i, 

 sporophyll ; v.b., vascular bundle ; :', integu- 

 ment ; 111, micropyle ; sm, wall of sporangium ; 



1 " Organisation, etc.," part viii., Phil. Trans. 1877, p. 254, Figs. 

 1 17 -1 19; part a. 1880, p. 518, Fig. 64. The identification of these 

 " seeds" with the Cardiocarpus of Brongniart is certainly incorrect. 



