XLIV] PITYOXYLON 229 



sparsely distributed. There would seem to be little difference of 

 importance between this species and wood referred to Cedroxylon. 

 The number of Cretaceous examples of Pityoxylon might be 

 considerably extended : for an account of French species reference 

 should be made to Lignier and to Fliche. 



Pityoxylon Pseudotsugae (Gothan). 



Gothan described this species, from South Nevada and prob- 

 ably of Tertiary age, as Piceoxylon Pseudotsugae^ : it is interesting 

 as a type of Pityoxylon agreeing closely with the recent genus 

 Pseudotsuga in the presence of spiral bands in the tracheids. There 

 are both vertical and horizontal resin-canals and the ray cells have 

 Abietineous pitting. Xylem-parenchyma occurs next the summer- 

 wood and the epithelial cells have thick walls, features in agree- 

 ment with Gothan's genus Piceoxylon. Bailey^ points out that in 

 the absence of spiral bands in the ray-tracheids the fossil species 

 resembles Pseudotsuga Douglasii, while in Pseudotsuga macrocarpa 

 the tracheids of the rays have spiral bands. 



Fritel and Viguier^ have described a species from Eocene beds 

 in the Paris Basin as Piceoxylon Gothani in which some of the xylem- 

 tracheids have spiral bands. 



Pityoxylon pulchrum (Cramer). 



A Tertiary species* originally described from material collected 

 by Sir Leopold MacClintock in Banksland as Cupressinoxylon 

 jtulchrum. A piece of wood in the Dublin Museum labelled 'from 

 Ballast Bay, Baring Island, given by Sir L. MacClintock' agrees 

 very closely with Cramer's type-specimen, and as the resemblance 

 extends to most of the anatomical characters, I believe it to be 

 the material on which C. fulchrum was founded. The chief 

 difference is that the Dublin wood has resin-canals as in the 

 specimen described by Cramer as Pinus MacClurii (?) Heer^; 

 in C. puhhrum no resin-ducts are recorded. On the other hand 

 in the sum of its characters the Dublin specimen agrees much 

 more closely with C. pulchrum. Annual rings well marked; 



1 Gothan (06=i). " Bailey (09) p. 54. 



=■ Fritel and Viguier (11) p. 63. 



* Cramer (68) p. 171, PI. xxxiv. fig. 1 ; PI. xxxvi figa. 6—8. 

 ^ Ibid. Pis. XXXV, XXXVI. 



