CARBONIFEROUS. 185 



connected by a long chain of varieties, which gradually pass into one another. 

 Some Botanists, however, still regard several of the names here placed under 

 Sigillaria tessellata as distinct species. 



The Collection contains several specimens showing the verticils of fruit- 

 scars. The alteration in the form and arrangement of the leaf-scars in the 

 region of the verticils is in some cases very marked. On a specimen from 

 Yorkshire the leaf-scars near the verticil of fruit-scars are much smaller and 

 more closely placed than on the other parts of the stem, where they are 

 separated from each other by half their own length. Those leaf -scars in the 

 immediate neighbourhood of the verticil are also much more elongated in 

 form, being only about half the breadth of the scars more distant from the 

 verticil. The form and arrangement of the leaf-scars in this species are 

 subject to more variation than in any other member of the genus. 



I am inclined to think that the Favularia nodosa (Bowman, MS.), L. and H., 

 is not specifically distinct from Sigillaria tessellata. 



The specimen identified as Sigillaria elegans by Brongniart, and of which 

 he described the structure (Observ. Sur. la Struct. Inter, d. Sigillaria elegans; 

 Archiv. du Mus. d'Hist. Nat. p. 405, pi. xxv.-xxviii. 1839), does not appa- 

 rently belong to this species. Eenault (Cours d. Botan. Foss. 1883, p. 14) 

 places it under Sigillaria Menardi, Brongt., but I prefer referring it to Sigil- 

 laria Brardii. It is to be noted, however, that one of Brongniart's figures of 

 Sigillaria Menardi (Hist. d. Ve"g6t. Foss. pi. clviii. fig. 6, not 5) is now recog- 

 nised as a young specimen of Sigillaria Brardii, Brongt. 



In the Collection are several specimens of Stigmaria conferta, Corda, which 

 I am disposed to regard as the root of Sigillaria tessellata. From the exami- 

 nation of these and other examples of this fossil, there appears to be a gradual 

 transition in the form of the scars from Sigillaria ornata to Stigmaria 

 conferta. As far as I know, the latter has in Britain always been found 

 associated with Sigillaria tessellata. This, of course, is no proof that it is the 

 root of that plant, but when taken in conjunction with the characters that 

 the specimens themselves show, it strengthens the probability of this view. 



Horizon. Coal Measures. 



Localities. British. Derbyshire : Biddings. Lancashire : near Man- 

 chester. Northumberland : Newcastle- on-Tyne. 

 Somersetshire : Radstock. 



Foreign. Bavaria : Langenbrucken. Belgium : Mons. Rhenish 

 Prussia ; Saarbrlick. Westphalia : Werne, near 

 Bochum ; Wattenscheidt ; Steele ; Langendreer. 



Stigmaria conferta, Corda. 



British. Northumberland : Newcastle-on-Tyne. Somerset- 

 shire : Camerton. 



Sigillaria Dournaisii, Brongniart. 



Sigillaria Dournaisii. 



Andrae, Jahrb d. Naturw. Vereines, Halle, 1850, p. 124. 

 Boulay, Terr. Houil. du Nord de la France, p. 40. 

 Bronguiart, Prodrome, p. 65. 



Hist. d. Veg6t. Foss. p. 441, pi. cliii. fig. 5. 



Bronn, Index Palseont. p. 1144. 

 Dawson, Acadian Geol. 2nd ed. 1868, p. 475. 



Quart. Journ. Geol. Soc. vol. xxii. p. 148. 



Canadian Nat. vol. viii. p. 436. 



Foss. Plants Lower Carb. Canada, p. 35. 

 Goldenberg, Flora Saraep. Foss. heft ii. p. 28, pi. vii. figs. 22-24. 

 Heer, Flora Foss. Helv. lief. i. p. 41, pi. xvi. fig. 2. 



Urwelt d. Schweiz, p. 5, fig. 1. 

 Lesquereux, Coal Flora of Pennsyl. p. 480. 

 Roehl, Foss. Flora d. Steink. Form. Westph p. 98 pi. vii. fig. 4. 



