RAVENHEAD COLLECTION IN THE BROWN FREE LIBRARY AND MUSEUM. 413 



which the leaves clothe the stem, it is seldom that one finds examples which show the 

 form of the leaves clearly. In the specimen I figure they are well shown at the point 

 marked with a + , and are enlarged five times at fig. 6a. The leaves are linear 

 lanceolate, single nerved, and taper to a sharp point. I have little doubt, however, 

 that their form will vary somewhat on different parts of the plant. 



Sigillaria, Brongt. 

 Sigillaria tessellata, Brongt. 



Sigillaria tessellata, Brongt., Hist. d. veget. foss., p. 436, pi. clvi. fig. 1 (?); pi. clxii. figs. 1-4. 

 Sigillaria tessellata, Zeiller, Flore foss. d. bassin liouill. d. Valenciennes, p. 561, pi. lxxxv. figs. 1-9 ; pi. 

 lxxxvi. figs. 1-6. 



Sigillaria mamillaris, Brongt., var. abbreviata, Weiss. 



Sigillaria mamillaris, Brongt., var. abbreviata, Weiss, Foss. Flora d. jiingst. Stk. u. d. Rothl., p. 165', pi. 

 xv. figs. 1, 2. 



Sigillaria Arzinensis, Corda. 



PL I. fig. 2. 



Sigillaria Arzinensis, Corda, Flora Protogma, p. 29, pi. lix. fig. 12 (figure inverted). 

 Sigillaria Arzinensis, Goldenberg, Flora Sarcepont. foss., Heft ii. p. 44, pi. x. fig. 14. 

 Sigillaria Arzinensis, Kimball, Flora from the Apalachian Coal Field, p. 16, pi. i. fig. 5. 

 Sigillaria Arzinensis, Schimper, Traite d. paleont. veget, vol. ii. p. 93. 



Description. — Ribs arched, separated by straight furrows ; leaf-scars ovate, lateral 

 angles distinct but not very prominent ; cicatricules slightly above the centre, the two 

 lateral straight or slightly lunate, diverging, the central punctiform. On the ribs, 

 extending from one leaf-scar to another, is a longitudinal band of very fine punctato- 

 granulate markings, and immediately above the leaf-scars are fine transverse corrugations. 

 Subepidermal surface longitudinally striate. 



Remarks. — The surface ornamentations of the ribs of this species are very delicate, 

 and unless the specimens are in a fine state of preservation they would not likely be 

 shown. I have indicated the appearance they present at PI. I. fig. 2a. Above the 

 scars the ornamentation is more pronounced, and assumes the form of fine transverse lines 

 which bend round the upper end of the leaf-scar. On account of imperfect preservation, 

 I can easily understand that this species will more frequently be found with a smooth 

 bark, and in this condition it would be difficult to distinguish it from Sigillaria ovalis, 

 Lesqx., # which may, perhaps, be only a form of Sigillaria Arzinensis, Corda. 



Stigmaria, Brongt. 

 Stigmaria ficoides, Sternb., sp. 



Stigmaria ficoides, Brongt., Class, d. veget. foss., p. 9, pi. i. fig. 7. 

 Stigmaria ficoides, L. & H., Fossil Flora, vol. i. pis. xxxi.-xxxvi. 

 Variolaria ficoides, Sternb., Vers., i. fasc. i. pp. 22 and 24, pi. xii. figs. 1-3. 



* Goal Flora, vol. ii. p. 495, pi. lxxi. figs. 7, 8. 



