1883. J Anomalous Oolitic and Palceozoic forms of Vegetation. 221 



of Scarborough, Whitby, and York. The result of these and other 

 studies was a memoir written more than thirty years ago, but not 

 published until 1868.* The conclusions at which I then arrived were 

 that the two very diiferent objects on the table before us were possibly 

 the male and female reproductive organs of some Dioecious plant ; 

 and from their apparently constant association in the Oolitic sand- 

 stone of Salt wick and Hawsker with the fronds and stems of the 

 Cycad, Zcmia gigas. I said " the inference that they are parts of one 

 plant, though incapable of proof, is forcibly suggested," " at all events 

 such suggestions will raise definite points for future investigation."! 



Fig. 1 represents the general aspect of what I believed to be 

 the Androecium or male organ. The globular structures a, a are 

 composed of a circular series of narrow, curved bracts, enclosing a 

 peculiar axis. Fig. 2 represents a section through the centre of this 

 organism, in which a, a are these bracts ; b is the central pyriform 

 axis, the greater part of which is invested by a cortical layer, c, of 

 long narrow tubes or cells, disposed vertically to the surface of the 



' organ. The peduncle (Figs. 1, d ; 2, d), which was sometimes branched, 

 as in Fig. 1, was clothed with shorter overlapping leaves or bracts 

 (Figs. 1 and 2, e). The supposition that the cortical layer (Fig. 2, c) 

 possibly bare antheridial organs, was rather inferred from the struc- 

 ture of the specimen represented diagramatically in Fig. 3. This 

 figure represents a section through the middle of a verticil of in- 

 curved bracts, a, which have coalesced at their bases into a cup-sbaped 

 peduncle h. This organism has never yet been found attached to any 

 other ; but what led me to infer that it was possibly a gynoecium or 

 female structure, was the aspect of the upper surface of the free 

 portion of each bract, which has the appearance seen in Fig. 4. The 

 raised central ridge a is arrested at 6 by a pair of oblong depressions, 

 which seemed so obviously adapted for bearing a pair of Cycad ean 

 ovules, that the possibility of such having been their possible 

 function could not well be overlooked. Still lower down (Fig. 3, c) 

 are pairs of little circular depressions arranged in parallel rows 



i which seem to indicate the former position of other unknown or^^ans. 



I In a memoir, published in the ' Linnean Transactions ' along with 

 mine, Mr. Carruthers proposed for the group of fossil Cycads to which 

 my plants appeared to belong, the generic name of Williamsonia • 

 and as the Cycad, whose stems and fronds were associated with my 

 fossils, was the Zamia gigas of authors, this plant, along with my 

 fossils, stood in his memoir as Williamsonia gigas, the type rei^resen- 

 tative of the new genus. 



^ Since the publication of the above memoirs, new interest has been 

 given to these curious fossils by the discovery that, whatever may be 

 their botanical af&nities, they represent a type that has been widely 



* ' Contributions towards the History of Zamia gigas, by W. C. Williamson 

 F.K.S.' 'Transactions of the Linnean Society,' vol. xxvi. p. 663. 

 t Loc. cit., p. 672. 



