200 THE BOTANICAL MAGAZINE. L y i. xxiy. m. 234. 



of the unusual shape of the leaf of Pinus yezoensis Stopes and 

 Kershaw which is elliptical in transverse section, the authors 

 say (Stopes and Kershaw, 1910. 1. c. p. 401.) : ' In the shape 

 of leaf, which is oval, w 7 ith no straight edge such as is found 

 in the Pinus usually, we see a suggestion that there may have 

 been only one leaf in the fascicle. The living P. monophylla is 

 more circular in outline, however, and we would do no more 

 than point out the suggestion afforded by the shape of the leaf 

 in P. yezoensis and note that it is also supported by the fact 

 that there is a single bundle in P. yezoensis, as there is in P. 

 monophylla, while there is usually a double one in the modern 

 pines with two or three needles in a fascicle.' Thus the leaves 

 in question upon which the hew Cretaceous pine species Pinus 

 yezoensis was established, seems to have not yet found exact 

 location to the definite portion of the axis ot the plant. Under 

 such circumstances I should like to propose an alternative view 

 that this fossil pine leaf of Stopes and Kershaw belonged to 

 a seedling of Pinus, and represented the primordial leaf. It 

 differs in the shape of the transverse section and in the anato- 

 mical structure from both cotyledonary leaves and fascicled 

 leaves of brachyblasts. According to Stopes and Kershaw, 

 the authentic specimen of the pine leaf in question is suggested 

 to have belonged to a monophyllous brachyblast, while accord- 

 ing to my alternative, it is referred to the main axis of the 

 plant. Aug. Daguillon (1890) showed that the primordial 

 leaves of the species of Pinus which he studied had an undivid- 

 ed single bundle with a well differentiated endodermis, generally 

 two lateral resin canals on the under side of the leaf even in 

 case there are many resin canals in fascicled leaves and none in 

 the cotyledonary leaves of the same plant, and no develop- 

 ment of sclerized hypodermic fibres even in case the cotyledo- 

 nary leaves of the same plant had it; and that the primordial 

 leaves have elliptical shape in transverse sections, while cotyle- 

 donary leaves are always triangular, and the fascicle leaves are 

 usually either semicircular or triangular. These characteristics 

 of the primordial leaves of Pinus singularly coincide with the 

 chief characteristics of the fossil species Pinus yezoensis and we 



