THANSACriONS Oi' THJi SECTIONS. 145 



his attention to the American work ; and to Prof. Balfour for hia kind notice in the 

 * Transactions of the Botanical Societj' of Edinburgh,' vol. xii. part i. page 176, both 

 proposing that it sliould " bear the name of the finder.'' lie thought it right to 

 state that -wherever he foimd iSfapJii/lopferis, the Sphenopteris (iffinis more or less 

 accompanied it ; however, the latter was most often found without Staphylopteris. 

 As well as at AVest Calder, Sfaphi/hpferis has been found at Slateford by the Olhcers 

 of the Geological Survey and by Mr. D. J. Brown at Straition, all near Ediubm-gh, 

 and all in the Calciferous Sandstone series. 



A large series of Sphenopteris and Staphyloplcris M'cre exhibited by the author 

 with drawino-s for illustration. 



0)1 some of the PJiysiolor/ical and Morphological -Features seen in the Plants 

 of the Coal-Measures. By Profes.sor W. C. Williamson, F.It.S. 



Proceeding from the starting point of the facts recorded in the comnmnicatiou 

 made to the Geological Section*, the author brought before the Biological Section 

 some morphological facts. He showed that even in young twigs of Lepidoclendron 

 the bark consisted of three very distinct layers, viz : — an inner parenchyma, a 

 middle proseuchyma of cousidercable proportionate thiclmess, and an outer paren- 

 chyma of which the leaves were expansions. The innermost portion, the inner 

 parenchyma, certainly represents a plane of genetic activity, along which the 

 multiplying cells add new laj'ers of vessels to the exterior of the vascular cylinder 

 on its inner surface, as it apparently increases as the number of pareuchymatoua 

 cells in the opposite directions. Externally to this parenchyma is the ])rosenchy- 

 matous layer, into which the inner parenchyma passes somewhat gradually, but 

 Avhich outwardly becomes a modified mass of prosenchymatous fibre, composed of 

 very long and narrow prismatic cells. At the first glance this layer looks like a 

 phellem or corky layer, but its origin is a different one. Its genetic plane is at its 

 outer surface, instead of occupying the position of the phellugeu of living barks. 

 The cells at this point become elongated radially into long fusiform ones, which soon 

 become subdivided by a regular series of vertical cell-walls, all of which are parallel 

 to each other and to the external surface of the stem. Subsequently each one of 

 these parallel cells becomes irregularly subdivided into a cluster of cells, the 

 partitions of which are vertical to the primarj^ series. In this manner, apparently, 

 additions are made on tlie inner side to the prosenchymatous layer, and on the outer 

 one to the subepidermal parenchyma. It thus becomes evident that the bark of 

 each of the Lepidodendroid stems possesses two parallel planes of genetic activity. 



It is obvious that Calainites certainty possesses the innermost of these genetic 

 planes ; and as the author's arborescent specimen exhibits no indication that the 

 second or prosenchymatous laj'cr has been increased from within, it becomes more 

 than probable that when yet more perfect specimens are discovered the second or 

 outer genetic plane will be found to be identical in all respects with what ia seen 

 in the Lepidodendra. 



The author concluded by calling attention to the fact that amongst a large number 

 of the coal plants their most specialized and characteristic type features were best 

 seen in their young state, the advance from youth to maturity being one from specia- 

 lized to generalized forms, the result of which was, that the author found it almost 

 impossible to identify detached fragments of wood or bark, and hence he regarded 

 all attempts to establish genera and species upon such fragments as absurd. 



On 6i(jantic Land-Tortoises and a Freshwater Species from the Maltese 

 Caverns, with observations on tlicir Fossil F'auna. By A. Leith ADiMS, 

 F.li.S., Professor of Zoology, Royal Colleye of Science, Biihlin. 



The author exhibited and made a few observations on bones of gigantic toitoisea 

 collected by Admiral Spratt and himself in the Maltese Caverns. 

 During the five years he was engaged in exploring the rock-cavities of Malta, 



* Svpra, p. 98. 



