380 ERNEST WARREN. 



cavities liave been formed hj the disaj)pearance of sucli incoiiiiiletely 

 transformed areas. 



Fig. 27.— X 100. PI. XXV. Mus. No. 228. Z. "Wood Bed,'" 

 False Bay. Longitudinal tangential section of jet-like substance show- 

 ing clearly the outlines of vessels (w.v.) and of the cells of medullary 

 rays {l.a.m.r.) 



Explanatory References. 

 A.t. ATitumn tracheide. b.s. Blackened silica, b.s.t.w. Blackened silica 

 in tracheide wall. c.c. Calcium phosphate cast. c.s. Colourless silica. 

 cup. Central space. e.S.f. Compressed spring tracheide. d.f. Dcpolari'z- 

 ing fibre, d.p. Dark portion with crossed prisms, e.a. Edge of autumn- 

 wood, g. Cavity of medullary ray gland filled with yellow matter. 

 /./. Inner layer of cast. i.m. Inner mass. i.s. Intertracheide space 

 filled with calcium phosphate! l.a.m.r. Less altered medullary ray. 

 I.e. Lenticular cavity, m. Matrix formed by coalescence of tracheide 

 walls, m.c. Microscopic crack. Hi. c.?r. Medullary cell wall. m.f. Micro- 

 scopic fracture. iH.r. Medullary ray. ni.}\. Medullary ray in jet-like 

 substance showing trace of cells. m.r.c. Medullary ray cells filled 

 with yellow matter, m.r.s. Medullary ray silica, o. Oxide of iron or 

 carbon, o.m.r. Oxide of iron in medullary ray. o.c. lo. Original cell wall. 

 o.t.w. Original tracheide wall, o.t.w.c. Original tracheide wall and outer 

 portion of cast. p.c. Parenchymatous cell communicating with pitted 

 vessel, p.f. Pnmary fracture filled with secondary deposit, p.r. Pitted 

 vessel, p.v.y. Pitted vessel filled with yellow matter. r.Hi.c. Remains 

 of medullary cell, r.vi.r. Remains of medullary ray. /•./. Rent tracheide. 

 r.t.t.ic. Remaining trace of tracheide wall. s.c. Scalariform vessel. 

 .-^.r.c. Solid calcium phosphate cast. s.f. Space filled with crystalline 

 calcium phosphate, s.fr. Secondary fracture extending through primary 

 cast and inner layer. s.S.t. Shattered spring tracheides. s.t.w. Silicified 

 tracheide wall. th. Thylose. t.m.r. Trace of medullary ray. u.S.f. 

 Uncompressed spring tracheide. v. Trace of vessel in jet-like substance. 

 lo.f. Wood fibre. lo.j^- Wood parenchyma. ic.sj). Weathered space. 

 u\v. Wood vessel, ij. Yellowish-red bituminous matter in fi))res and 

 medullary cells, y^. Yellowish-red bituminous matter between fibres. 

 il.p.v. Bituminoiis matter in pitted vessels. 



