1848.] BRODIE ON THE DRAGON-FLY. 31 



Mr. Dawes stated, that specimens he had obtained clearly showed 

 that the Calamite as usually met with exhibits merely the interior 

 shape of the woody part of the plant, the supposed leaf-scars at the 

 articulations being the fractured portions of certain large rays of mu- 

 riform tissue which pass through the ligneous system in a similar 

 manner to what has been observed in the pseudo-vascular sheath of 

 Stigmaria, these rays being connected with verticillate areolae met with 

 on the exterior of the fossil. The ligneous portion is found in some 

 specimens to occupy about one-half of the diameter, although usually 

 much less. It consists of tubular tissue, which although distinctly 

 scalariform, has nevertheless in the transverse section a radiated 

 structure together with the concentric rings of Exogens ; and in addi- 

 tion to the leaf-cords already mentioned, there are numerous fine 

 medullary rays which either alternate with, or intervene, every second 

 or third row of the ligneous or scalariform tissue. He also men- 

 tioned, that occasionally the striae upon these vessels become reticu- 

 lated, so as to resemble in some respects the Pinites ; and again, that 

 there appears to be a further affinity with the latter fossils, and with 

 the Coniferse generally, for these peculiar markings are usually to be 

 observed only in the direction of the ray. The phragmata at the 

 joints, which have been considered by some writers as probably re- 

 presenting the thickness of the wood, he considers now prove to be 

 merely thin lateral inward extensions of the ligneous system, the 

 converging lines being a continuation of the perpendicular ribs, and 

 having a similar origin ; consequently the articulations will not be ob- 

 served upon the exterior of the plant. With respect to the supposed 

 fistular character of the stem, Mr. Dawes states that he is in pos- 

 session of sufficient evidence to prove not only that such was not the 

 case, but that, in addition to cellular tissue, there are also indications 

 of vascular bundles within the central column. The specimens he 

 has hitherto met with retaining these tissues are very imperfect, but 

 there are appearances in the arrangement which he regards as show- 

 ing an affinity with Endogens. This he says we might have been 

 led to expect from certain external characters observed by Messrs. 

 Lindley and Ilutton ; and thus in all probability these interesting 

 plants of the carboniferous epoch will, he thinks, prove to be a link 

 connecting in some measure the three great classes of the vegetable 

 kingdom. 



3. Notice on the Biscovery of a Dragon-fly and a new species of 

 Leptolepis in the Upper Lias near Cheltenham, with a few 

 remarks on that Formation in Gloucestershire. By the Rev. 

 P. B. Brodie, M.A., F.G.S. 



As I have already described the position and structure of the upper 

 lias and its organic contents in Gloucestershire*, my chief object in 

 the present brief communication is to announce the occurrence of a 



* History of the Fossil Insects in the Secondary Rocks of England, p. 55, et seq. 



