XL] MALE FLOWERS 51 



It has been suggested that the seed-bearing shoots, which 

 Carruthers named Bfiania, from Jurassic beds on the Yorkshire 

 coast may have belonged to a member of the Ginlf goales, but it is 

 at least equally probable that Beania is Cycadean and possibly 

 the seed-bearing axis of Nilssonia. The genus is described in 

 Ch. xxxviii^. It is possible that specimens from Cretaceous and 

 Jurassic rocks regarded by Heer as male flowers of Ginkgoites 

 sibirica and other species, also specimens described by him as 

 Antholithus Schmidtianus^, may be fertile shoots, which bore 

 seeds and not microsporangia, belonging to GinJcgoites or some 

 other member of the Ginkgoales: the nature of these fossils is, 

 however, uncertain and they are described under the generic 

 name Stenorachis . 



a. Male Flowers. 



As with seeds so also with regard to the microsporophylls 



our information is scanty and indecisive. Nathorst^ first suggested 



that some small carbonised bodies from Yorkshire Jurassic beds 



figured by Phillips* as 'unknown leaves' are probably fragments 



of male flowers of some species of GinJcgoites. The specimen of 



which Phillips figured a small portion is shown in fig. 654, B ; it 



consists of a slender axis with several short and partially broken 



lateral branches bearing terminal groups of oblong bodies 4 mm. 



long and 1 mm. wide, 2 — 4 in each group : these suggest comparison 



with pollen-sacs with longitudinal dehiscence, and the habit of the 



whole fertile shoot agrees with that of a male flower of Ginkgo 



biloba. In the recent species the microsporangia are only about 



2 mm. long, but in the occurrence of two to four microsporangia 



on a single microsporophyll the resemblance between the fossil 



and recent form is fairly close^. Unfortunately it has not been 



possible to make any preparations of the cuticularised remains 



showing microspores, and while the probability is that the oblong 



bodies are microsporangia it is not impossible that they are small 



seeds. A collection of identical bodies showing what appears to 



be a median line of dehiscence is illustrated in Part I of The Jurassic 



Flora of Yorkshire^. A larger specimen is shown in fig. 654, A; 



1 Vol. ni. p. 502. 2 jjeer (^2) A. p. 21, PI. ix. 



3 Nathoret (80) A. p. 75. * Phfllips (29) A. ; (75) A. PI. vii. fig. 23. 



5 See page 5. « Seward (00) E. p. 260, fig. 45. 



4—2 



