XLIV] CUPRESSINOXYLON 189 



very cleacly the appearance of xylem- or resin-parenchyma as 

 seen in transverse, radial and tangential section. The presence 

 of dark contents renders these cells conspicuous in transverse 

 section (A) and both contents and cross-walls are seen in the longi- 

 tudinal sections (B, C). In fig. 715, B, the opposite and scattered 

 bordered pits are shown on the radial walls of the tracheids with 

 an occasional tendency to an alternate arrangement. Goeppert 

 founded his species Pinites Pritchardti^ on wood from Lough Neagh, 

 the generic name being altered by Kraus to Cii-pressinoxylon^. 



Kraus* enumerates 46 recent species of Conifers with wood of 

 the Cupressinoxylon type and Beust* mentions 37 species. As 

 used by most authors Cupressinoxylon includes members of the 

 Cupressineae (in the wide sense as used on page 124), Podocar- 

 pineae, Abies Webbiana, and some other recent genera. As 

 already stated Gothan has essayed the difficult task of defining the 

 genus in such a way as to restrict the wood so named to a smaller 

 number of recent Conifers, recognising as distinct genera certain 

 species previously included in Cupressinoxylon, e.g., Taxodioxylon 

 (= Cupressinoxylon Sequoianum Merck. ^), Podocarpoxylon (= C. 

 Hookeri Arb.^), Xenoxylon {=^ Cupressinoxylon Barberi Sew.'): 

 these and other species formerly included in Cupressinoxylon are 

 distributed among genera not always well defined but instituted 

 with a view to increase the value of fossil species considered in 

 relationship to recent types. 



[Paracupressinoxylon. Holden.] 



Miss Holden^ has proposed a new generic name, Paracupressi- 

 noxylon for wood which agrees with Cupressinoxylon in having 

 xylem-parenchyma scattered through the year's growth but 

 differing in the Abietineous pitting of the medullary-ray cells and 

 in the absence of Sanio's rims. In Paracupressinoxylon are in- 

 cluded two species, P. cedroides and P. cupressoides, both Jurassic 

 and the latter also Cretaceous in age, which appear to differ too 

 much from one another to be referred to one genus. Both species 



1 Goeppert (50) p. 220. ^ Kraus in Schimper and Schenk (72) A. p. 376 



3 Kraus (64). ^ Beust (85). 



» Mercklin (55) PI. xvii. « Arber (04) ; Gothan (08) p. 7. 



' Seward (04) B. p. 60, PI. vii. 



« Holden, R. (13^) p. 537; (14) p. 173. 



