442 STRUCTURE AND AFFINITIES OF LEPIDOSTROBI. 



of Lepidodendron, each from two or three inches to a foot long and 

 from two to five inches in diameter, from the Staffordshire coal-fields, 

 all of them containing one or more fragments of Lepidostrobi* These 

 Lepidostrobi are of various lengths, they run parallel to the stem in which 

 they are enclosed, are of all ages, and in various stages of decomposition. 



In one large stem, figured at plate 9, fig. 2, and plate 10, fig. 1, 

 the remains of upwards of thirty Lepidostrobi are crowded together 

 with broken-up portions of the bark and of other parts of the Lepi- 

 dodendron itself. When they are solitary, which is very frequently the 

 case, they resemble the vascular axis of the Lepidodendron, and are 

 usually taken for such ; but a very slight examination suffices to shew 

 their true nature. 



Usually the fragments of Lepidostrobi are not more than half an inch 

 long, and very frequently are mere discs ; so that though there is often 

 the appearance of one several inches long, and traversing the whole 

 length of the fragment of Lepidodendron, it will generally be found 

 that this is owing to two being placed each at an extremity of the 

 truncheon, and opposite to one another. That all were exceedingly 

 brittle cannot be doubted, for no modern cone of any natural order 

 could be broken up into the shallow discs which many of these fossils 

 present. This brittleness of Lepidostrobi, combined with that of Lepi- 

 dodendron, is in consonance with the remark I have elsewhere made, 

 that the tribes of plants that were converted into coal, were all of a 

 singularly compressible and succulent texture. 



It is difficult to account for the presence of these fragments of Lepi- 

 dostrobi, and especially of so many in one Lepidodendron stem as are 

 shewn in plate 10, fig. 1. We can but conjecture that the trunks of 

 the latter were erect stumps whose interior was hollowed out by decay, 

 that these stumps were covered with water, charged, so to speak, with 

 myriads of broken fragments of Lepidostrobi and other vegetable matter, 

 which were washed by the fluid into the stumps. These points, how- 

 ever, demand a separate consideration, and will be better understood 

 by a reference to the figures in plate 9, and those of transverse sec- 

 tions of the same fossils in plate 10, bearing in mind that the Lepido- 

 dendron stems or stumps are stuffed throughout with fragments similar 

 to those figured in plate 10." 



1. The stumps appear to have been rooted and erect, and to have 

 received the cone fragments into their cavity, as fern fronds find their 

 way into the axis of Sigillarice. Were the stumps mere prostrate por- 



* There is in Lord Stamford's Museum, at Enville Hall, a very valuable collection of 

 coal fossils, made by Mr, Beckett, of "Wolverhampton : amongst them is a cylindrical 

 specimen of Lepidodendron, containing three species of shells labelled Unto aquilinvs, 

 Modiola carinata, and Mytilus triangularis. 



