XLVn] SCIADOPITINEAE 365 



fossil it would be referred to Brachyphyllum. The figured specimen 

 shows the variable form and size of the leaves and there is 

 good reason to believe that the plants represented by the frag- 

 ments included in one or other species of Sphenolepidium were 

 characterised by a considerable range in the habit of the foliage- 

 shoots, a fact which renders of little importance the separation 

 into S. Kurrianum and S. Sternbergianum based on the form of the 

 leaves in detached branches. The small cones borne terminally on 

 slender branches resemble superficially the cones of Aihrotaxis, but 

 no facts are available as to the structure of the cone-scales and 

 there is no evidence on which to found an opinion as to the position 

 of the genus. 



SCIADOPITINEAE. 



Though several fossil plants have been compared with the 

 existing species Sciadofitys verticillata, in no case is there any con- 

 clusive evidence of the occurrence of this type of Conifer. Schmal- 

 hausen founded the genus Cyclopitys''- for impressions of shoots 

 from Eussia bearing whorled hnear leaves which he believed to be 

 closely aUied to or generically identical with Sciadofitys. Zeiller^, 

 who brought forward strong arguments for assigning the strata 

 regarded by Schmalhausen as Jurassic to the Permian period, 

 considers Cyclopitys to be an Bquisetaceous plant. DetacheH hnear 

 leaves similar to those of Cyclopitys are abundant in many Jurassic 

 floras and, as Nathorst* says, they may be compared with several 

 recent genera including Sciadopitys, but without anatomical data 

 accurate determination is impossible. It is stated by Schenk* that 

 the Cretaceous leaves described by Heer as Pinus Crameri agree in 

 their epidermal features with the foHage of Sciadopitys, but in this 

 as in other cases generic identity or even close relationship has not 

 been demonstrated. Goeppert and Menge^ describe some single 

 leaves preserved in Baltic amber as Sciadopitytes linearis and 

 S. glaucescens; they speak of the leaves as having a single vein on 

 the upper face and two veins on the lower surface though it is not 

 clear what morphological feature is represented by the 'veins.' 



1 Schmaltausen (79) A. p. 39. ^ ZeiUer (96) A. p. 477. 



3 Nathorst (97) p. 19. ' Schimper and Schenk (90) A. p. 293 



' Goeppert and Menge (83) A. p. 36, PI. xin. figs. 117—123. 



