LATE GLACIAL PLANTS OF THE LEA VALLEY 195 



with doubt by Dr. Lewis ; badly-preserved achenes of R. rejjens 

 might easily be mistaken for B. acris. 



Draba incana. The thin, tough, delicately-veined, oval valves 

 of this plant are very abundant at three different localities in the 

 Lea Valley. They are equally common in the Scottish Late 

 Glacial deposits, though until now their true nature has not been 

 recognised. They are probaijly the '• sn^ail petal-like objects " 

 mentioned by Dr. Lewis. ■■ . . . 



'Silene Gucuhalus and S. cmlata, sp. nov. Dr. Lewis mentions 

 two species of this genus, which he refers to S. maritima and 

 Silcne sp. : " one much-crushed specimen, species not determin- 

 able." I find a few seeds of S. Gucuhalus at Angel Eoad and 

 Hedge Lane, and these may correspond wdth Dr. Lewis's undeter- 

 mined crushed seed from Ponder's End, though I have not yet seen 

 a specimen from that locality. In addition to these seeds numerous 

 seeds of another Silcne were found at all four localities, which may 

 be the plant determined as S. maritima. It is quite distinct, how- 

 ever, from S. maritima, and the discovery of the calyx and capsule, 

 as w^ell as the seed, show that it is an unknown species belonging 

 to the section Mclanclryum and allied to our own living S. nocti- 

 fiora, though the sculpture of the seed is very different. I can 

 find no other living species at all near to it, and must therefore 

 describe it as new. 



SiLENE C^LATA, Sp. nOV. 



Calyx late ovoideus, superne angustatus, inferne aequabiliter 

 contractus, 16 -f mm. longus, 10-nervis, 5-dentatus. Capsula 

 ovoidea, inflata, infra baud umbilicata, 9 mm. longa, carpophoro 

 quintuplo longior, in valvas sex triangulares dehiscens. Semina 

 reniformia, lateribus complanata lacunosave, dorso rotundata, 

 1'3 mm. longa, 1*3 mm. lata, tuberculis lateralibus elongatis 

 radiatis, jugis acutis tenuibus, saepe extremitatibus furcatis, 

 suturis plicatis, lobis circiter duodecim, tuberculis dorsahbus 

 rotundatis obtusis, in lineas circa sex dispositis. 



Calyx large, broadly ovate, narrowed above, and 5-toothed, 

 regularly contracted into the pedicel below ; 10-veined, secondary 

 veins few ; teeth broken off", but apparently awl-shaped. 



Length = 16 mm. (without the teeth). Two specimens. Temple 

 Mills. 



Capsule ovate, inflated , not umbilicate below, 6 times the length 

 of the carpophore,- smooth, polished, faintly striate on the teeth, 

 dehiscing in six triangular valves. 



Length = 9 mm. One specimen. Ponder's End. 



Seed reniform or roundly triangular, sides flattened or indented, 

 back rounded ; tubercles on the sides strongly radiate, with sharp 

 thin ridges, often forked at the ends ; sutures sharply and deeply 

 foliate with about twelve lobes ; dorsal tubercles roundly oval, 

 blunt, in about six rows. 



Length = 1-3 mm., breadth =: 1-3 mm. Common at Angel 

 Road, Hedge Lane, Ponder's End, Temple Mills ; unknown else- 

 where. . . . 



* Q. J. G. S. vol. Ixviii (1912), p. 229. 



