CHAPTER XXXIV. 



CORDAITALES. 



C. PITYEAE. 

 Pitys. Witham. 



THIS generic name in the form Pitus was first used by Witham 1 

 for some petrified pieces of large stems from Lower Carboniferous 

 strata in the south of Scotland (Berwickshire). In an earlier 

 paper Witham 2 gives an account of the beds on the banks of the 

 Tweed from which the specimens of Pitys and other plants were 

 obtained. The name was revived by Goeppert 3 as a substitute 

 for Pissadendron* adopted by Endlicher and Unger: Scott 5 

 employed the older name in the account of his investigations, 

 which have added greatly to our knowledge of Witham's types. 

 The distinguishing characters of Pitys are: the Araucarian 

 pitting of the secondary xylem, the large pith, the occurrence 

 of numerous small primary xylem strands of mesarch structure 

 in the peripheral region of the pith, and the simple nature of the 

 leaf -traces. Nothing is known of the extra-stelar tissues, and 

 beyond the fact that the species were arborescent we have no 

 information with regard to the foliar 6 or reproductive organs. 



Pitys antiqua Witham. 



In 1899 Scott 7 published a preliminary description of some 

 sections in the possession of Dr Kidston from Lennel Braes 

 (Berwickshire : Calciferous series) under the name Araucarioxylon 

 antiquum, but in the more complete account the name Pitys 8 

 is adopted. The following description is based on Scott's paper 



1 Witham (33) A. pp. 37, 71. 2 Witham (30). 



3 Goeppert (81) p. 403. 4 Endlicher (47) p. 297. 



6 Scott (02) p. 346. 6 See footnote p. 288. 



7 Scott (99 2 ); Witham (33) A. Pis. m. vm. xvi. 



8 Scott (02), p. 346, Pis. i., n., v., vi. 



