190 ME. C. IIKLD A>'D ME. J. GEOTES OX THE [vol. Ixxvii, 



The rest of the vegetative remains found, irrespective of the 

 nodes, which Avill be dealt with separately, appear to belong to four 

 t^'pes, as follows : — 



Type B. — Short fragment of a small stem, shown in section in 

 PI. YI, fig. 13, about 375 /x in diameter (including cortex), with 

 eight markedly non-contiguous cortical cells, the cortex being 

 evidently haplostichous in character, that is, having primary series 

 only developed, so that the number of rows of cortical cells equals 

 that of the branclilets. The cells are not collapsed. 



Type C (PL VI, fig. 11). — Several short portions of a medium - 

 sized stem about 500 /x in diameter, with eight to ten cortical rows, 

 usually non-contiguous, and for this reason, as also from the 

 number of rows, presumably haplostichous. 



Type D (PI. Yl, figs. 15 & 16). — A few small fragments of a large 

 type of stem, which can only be conjectured to be about 1300 /x 

 in diameter, no complete cylindiical portion having been found. 

 The cortical cells are very large (about 160 /j. in diameter), lirm 

 and thick-walled, and their number would probably be about 12. 

 The cortex would appear to be irregular from the portions 

 shown in fig. 15, and the cells are nodulose. There is no evidence 

 as to whether the cortex is haplostichous or diplostichous : but 

 perhaps the number of rows m^ay be regarded as suggesting that it 

 belono:s to the former cates^orv. The diameter of the stem, if 

 correctly estimated. Avould suggest a plant of about the stature of 

 Cliaro. ri'dis. 



Type E (PI. YI, figs. 17 & IS). — A few portions of small to 

 medium- sized, hollow, cylindrical bodies, belonging presumably to 

 an ecorticate Characeous plant, with small elongated bodies, re- 

 sembling the spine-cells of recent species, attached and projecting 

 at about a right angle. The nature of these latter has not been 

 made out. and it is probable that they are foreign bodies. As they 

 do not proceed from nodes, they cannot well be spine-cells, and as 

 they do not commimicate by a pore at the base with the internodal 

 cell on which they occur, they evidently are not akin to the rosette- 

 cells of Clavator. We hope that the discovery of more specimens 

 of this tyjDe may result in an elucidation of its peculiarities. 



The bodies shown in PI. YI, fig. 19 are probably stem-nodes fi'om 

 which the branclilets have been separated. If this be the case, the 

 number of branclilets, as indicated by the scars, would be nine to 

 eleven. Pig. 20 shows what is apparently a less complete node of 

 a much larger species, perhaps Tyj^e D. 



The specimens already mentioned were all obtained from the 

 Limestone-Band. 



The stem-node with bases of branchlets attached ('PI. YI, fig. 21), 

 obtained from the Rodent-Bed, belongs apparently to an ecorticate 

 plant. The interior diameter of the stem is about 300 /x. the 



