XL VIII ] PITYOCLADUS 379 



which afford no evidence as to the nature of the axis. The specimen 

 from the Stockholm Collection represented in fig. 775, from the 

 Khaetic rocks of Scania, is especially interesting as affording one 

 of the few examples of leaves of the type known as Pityophyllum 

 longifolium attached to an axis covered with short scales. The 

 lamina varies from 1 to 5 mm. in breadth and may be broader : as 

 seen in the enlarged portion the lamina is transversely wrinkled, an 

 appearance characteristic of most forms of the broader Pityo- 

 phyllum leaves and probably produced by contraction on drying. 

 There is little difference between this species and the leaves figured 

 by Nathorst from Scania as Schizolepis Follini. An accurate 

 specific delimitation of Pityophyllum leaves is hopeless. Detached 

 leaves (fig. 776) similar to those shown in fig. 775 are recorded by 

 Moller from Lower Jurassic beds in Bornholm, by other authors 

 from Jurassic strata in Turkestan 1 , South Russia 2 , Oregon 3 , Spitz- 

 bergen 4 , and elsewhere. 



Pityodadus Schenki Seward. 



Schenk 5 also refers to Schizolepis several specimens of branches 

 and leaves as well as cones which he includes in Schizolepis Braunii 

 Schenk. The larger branches bear leaf-cushions and short lateral 

 shoots with scale-leaves at the base, and in some examples tufts of 

 needles occur on the short shoots. A specimen described by Braun 

 as Isoetes pumilus is identified by Schenk in his monograph of the 

 Rhaetic Flora 6 as a leaf-bearing shoot like that of a recent Pine. 

 The Swedish specimen represented in fig. 775, also of Rhaetic age, 

 is similar to those included by Schenk in Schizolepis Braunii. 



Pityodadus kobukensis Seward. 



This species originally described from the Jurassic beds on the 

 Kubuk River in Chinese Dzungaria as Pinites 1 is founded on 

 branches bearing short shoots almost identical with P. Schenki. 

 Short shoots not more than 1 cm. long are borne spirally on a 

 thicker axis and covered with small leaf-scars (fig. 777) exactly 

 as in the corresponding shoots of Cedrus or Larix. With the 



1 Seward (07') B. p. 32. 2 Thomas (11) p. 78, PL vn. figs. 5861. 



3 Fontaine in Ward B. (05) PL xxxv. 4 Nathorst (97). 



5 Schenk (67) A. PL XLIV. figs. 1 4. 6 Ibid. PL XLIV. fig. 2. 



7 Seward (11) p. 54, PL iv. figs. 4751; PL v. fig. 65. 



