276 



AEAirCAKINEAE 



[CH. 



Pagiophyllum peregrinum (Lindley and Hutton). 



This species, first named by Lindley Araucaria peregrina^, was 

 founded on material from the Lias 

 of Lyme Regis in Dorsetshire^. 

 It is possible that the generic 

 name chosen by Lindley correctly 

 expresses the position of the 

 species, but decisive evidence is 

 lacking. Vegetative shoots bear 

 crowded imbricate, spirally dis- 

 posed, leaves tetragonal in section, 

 broadly triangular, sometimes fal- 

 cate and more or less appressed to 

 the stem in the lower portion of 

 the lamina (fig. 744). There is a 

 distinct dorsal keel and occasion- 

 ally rows of papillae are visible 

 on the lamina ; the apex is obtuse 

 or acute. The leaves vary consi- 

 derably in size and shape. Zeiller* 

 describes the cuticle of the dorsal 

 and ventral surfaces of some 

 leaves on Permian specimens from 

 Blanzy : the stomata occur in 

 longitudinal rows on the lower 

 face only, the guard-cells being 

 usually at right-angles to the long 

 axis of the leaf. 



In habit this species agrees 

 closely with Elatides William- 

 sonis, a Middle Jurassic type; it 

 occurs in Jurassic rocks of Eng- 

 land, France, Germany, Italy, and 

 elsewhere, the oldest recorded ex- 

 amples being those described by 



Fig. 744. Pagiophyllum peregrinum. 

 (British Museum ; nat. size.) 



1 Lindley and Hutton (33) A. PI. Lxxxvni. 



2 Seward (04) B. p. 48, PJ. v. ; Saporta (84) p. 383, Pis. 173—176, 



3 Zeiller (06) B. p. 219. 



