278 BOTAXICAL GAZETTE [October 



complete summaries of these investigations are given by Radais 

 (2) and Worsdell (11). 



Van Tieghem (9) in 1869 was the first to attack the problem 

 from the standpoint of vascular anatomy. He studied forms from 

 all the six large groups. He concluded that the megasporophyll 

 in all Coniferales is a compound structure. The seminiferous 

 scale represents the first and only leaf of an axillary shoot, as the 

 vascular supply to the scale is arranged in an arc. The ovules 

 are borne on the dorsal side of the leaf except in Araucaria, where 

 the ovule is refiexed toward the ventral side and hence appears 

 to be located between the bract and scale. In the Podocarpineae 

 and Taxineae the leaf is reduced to such an extent that it is repre- 

 sented practically only by the ovule. In Podocarpus the leaf is 

 folded on its dorsal surface to form an anatropous ovule, while in 

 Phcrosphaera, species of Dacrydium, Phyllocladus, and the Taxineae, 

 the leaf remains erect and the ovule is orthotropous. The inver- 

 sion of the ovule in certain forms is probably related to the greater 

 elongation of the sporophyll beneath the ovular insertion in those 

 forms. 



Strasburger (6, 7) in 1872 and 1879 gave comprehensive 

 descriptions of forms from all the groups. He held that in all cases 

 the ovule-bearing organ is an axillary structure. In Taxus and 

 Torreya the ovule is borne at the end of a secondary leafy shoot; in 

 Cephalotaxus the secondary shoots are reduced to ovules. In the 

 podocarps the secondary shoot is leafless and often reduced to an 

 ovule as in Phyllocladus, or provided with a stalk as in Dacrydium 

 and Podocarpus. In the Araucarineae it appears as if a stalk 

 bearing an inverted ovule were fused to the dorsal side of the bract. 

 In Cuuninghamia, which he classified with the Araucarineae, there 

 is a fusion of an inflorescence to the bract. In the Abietineae 

 the scale is a flattened axillary structure which is folded inward 

 and hence bears the ovules inverted. The two ovules suggest 

 that the axillary shoot is an inflorescence, a primary and two 

 secondary shoots similar to the two-flowered inflorescence in 

 Cephalotaxus. In the Cupressineae and Taxodineae the scale and 

 bract are fully welded together. Where many ovules occur, as 

 in Cuprcssus. he left it undecided whether the ovules represent 



