252 Mr. R. Kidston on the Relationship 



Ulodendron Lucasii, Buckland, Geol. & Mineral, vol. ii. p. 93, pi. Ivi. 



fig. 4. 

 Lepidophlo2os pai-vus, Dawson, Acad. Geol. 2nd ed. p. 470, fig. 170^ 



(1868) ; id. Quart. Journ. Geol. Soc. vol. xxii. p. 163, pi. xi. fig. 50; id. 



Canad. Natur. vol. viii. p. 453 ; id. Quart. Journ. Geol. Soc. vol. xxx. 



p. 216 ; id. Foss. Plants of Lower Carb. & Millstone Grit of Canada, 



p. 38. 

 Zepidophloios tetragonus, Dawson, Acad. Geol. 2nd ed.p. 490, fig. 170 rf 



(18(^8) ; id. Quart. Journ. Geol. Soc. vol. xxii. p. 164, pi. x. fig. 49 ; 



id. Canad. Natur. vol. viii. p. 453 ; id. Foss. Plants of Lower Carb. 



& Millstone Grit of Canada, p. 37. 

 Lepidodendron salebromm, Wood, Trans. Amer. Phil. Soc. vol. xiii. 



p. 345, pi. viii. fig. 6. 

 Halonia disticha, Morris, Trans. Geol. Soc. 2nd ser. vol. v. p. 489, 



pi. xxxviii. fig. 1. 

 Siqillaria Preuiana, Eomer, Palaeontograpbica, vol. ix. p. 42, pi. xii. 



fig. 7 (1862). 

 Sigillaria pe)-plexa, Wood, Trans. Amer. Phil, Soc. vol. xiii. p. 345, 



pi viii. fig. 7. 

 Sigillaria 3Ienardi, Lesquereux, Geol. Survey of lUin. vol. ii. p. 450, 



pi. xliii. 



Description. Leaf- scars rhomboidal, contiguous, their trans- 

 verse diameter slightly greater than their vertical diameter, 

 placed on slightly elevated cushions, whose size but little ex- 

 ceeds that of the leaf-scar. Upper and lower angles of leaf- 

 scar rounded, lateral angles sharp and prominent. Vascular 

 impressions situated towards the upper part of the leaf-scar ; 

 central punctiform, the two lateral lunate. Certain branches 

 bear two opposite vertical rows of large (Ulodendroid) scars, 

 those of one row alternating in position with those of the 

 corresponding vertical row. Large scars more or less oval, 

 usually touching each other. Bark generally fissured longi- 

 tudinally, especially in older examples. Decorticated branches 

 also exhibit longitudinal fissures and show on their surface 

 small " dots " arranged in quincuncial order. Leaves single- 

 nerved, grass-like. Fructification (sessile ?) cones attached 

 to the vertical rows of large scars. 



Remarks. I have found associated with this species peculiar 

 (sessile ?) cones (at least I have never seen them attached to 

 stems or twigs'), which I believe to be the fructification of 

 this species. They appear to differ from the cones of Lepido- 

 dendron, and are the same as those figured by Brongniart 

 (Hist. d. veget. foss. vol. ii. pi. xxii. figs. 2, 3, and 8*). 



As far as known to me, the ramification of this species has 

 not been observed, nor yet the termination of the brandies. 



This species was first figured as a Lepidodendron, without 

 any description, by Konig, about 1825. Bronn is the only 



* On the fructification of Sigillaria, see ZeiUer, Ann, des Sci. nat. 

 6"= ser. Bot. vol. xix. p. 256. 



