96 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 



varies according to the amount of lateral pressure to which they 

 have been subjected.^ The cones have evidently been stalked. 



On the form of Sigillaria Brardii, described by Gerraar as 

 Sigillaria spinulosa," are a number of small circular scars with a 

 i-aised margin and central depression. These occur without any 

 definite order, are either single or in pairs, and are generally 

 placed below the leaf-scars and not far distant from them. 

 Owing to the absence of lateral pressui-e these small scars on 

 forma spinulosa are always circular. They were supposed by 

 Germar to be the scars of deciduous spines. Schimper^ and 

 Renault,^ however, think they are the scars of aerial rootlets, and 

 that view was shared in by Weiss and Sterzel.^ 



I am more inclined to regard these scars as cone-scars, and 

 similar to those on Sigillaria Brardii, which I think un- 

 doubtedly mark the position of deciduous stalked cones.^ 



Renault, in describing a specimen of Sigillaria Brardii, on 

 whose cone-scars were still attached fragments of small branches, 

 1 to 2 cm. long by 5 mm. in diameter, states that these spring 

 perpendicularly from the stem, and bear small foliage cicatrices, 

 which are distant from each other, instead of being contiguous 

 like those of the main stem. It is certain here that the scars in 

 question did not bear aerial rootlets, and one appears to be 

 justified in believing that, whatever organ the small circular 

 scars between the cushions bore on Sigillaria Brardii, the same 

 organ was most probably borne by the similarly-formed scars in 

 Sigillaria Brardii for'tna spinulosa. 



In the other arrangement of the fructification the cones were 

 borne in two opposite vertical rows, the cones on one side 



1 Kidston, Proc. Roy. Phys. Soc. Edin., Vol. XIII., PI. VII., figs. 2, 2a. 



2 Germar, Vers. d. Sieink. v. Wettiii u. Lobejun, Heft. V., p. 28, PI. XXV., 

 figs. 1-2. Eefigured by Weiss and Sterzel, I.e., PI. X., fig. 50; PI. XL, 

 fig. 50a. 



^ Schimper, Traite d.vai6ont. v6g6t., Vol. II., p. 102. 1870. 



* Renault, Cours d. hotan. joss., 1881, p. 131. 



" Weiss and Sterzel, I.e., p. 107. 



« For figures see — Zeiller, V6g6l. foss. terr, houil. de la France, PL 

 CLXXIV., fig. 1; Renault, Coun d. hotan foss., 1881, PI. XVII., fig. 1 ; 

 Kidston, Proc. Boy. Phys. Soc. Edin., Vol, XIII., PI. VII., figs. 2 and 

 26 ; Sterzel and Weiss, I. c. 



