XXX] WHITTLESBYA 131 



fertile are microspore-bearing leaflets of Pteridosperms, possibly 

 of some MeduUosan plants. The leaflets of Whittlesey a agree in 

 form fairly closely with those of Potoniea adiantiformis Zeill. 

 described on a previous page^ as the male organs of a Pteridosperm. 

 The specimens described by Lesquereux from Pennsylvania 

 as W. integrifolia and W. undulata are less satisfactory than 

 W. elegans. The Arkansas species W. microphylla^, characterised 

 hj the obcuneate form of the lamina, is said to occur not only 

 as detached leaflets but in loose bunches at the ends of slender 

 axes, a circumstance favourable to the suggestion, based on the 

 recently described Enghsh specimens, that the Whittleseya leaves 

 may be fertile pinnules of a Pteridosperm frond. Among other 

 species attributed to Newberry's genus is W. hrevifolia Wh. from 

 Nova Scotia* with much smaller broadly triangular leaves 7 mm. 

 long exclusive of the petiole and 8 mm. broad at the distal end 

 (fig. 428, B). Dr Matthew* has also described a Canadian species 

 W. concinna from New Brunswick in beds assigned by Dr Stopes* 

 to the Westphahan series. 



Whittleseya fertilis Kidston. 



Since the discovery of Whittleseya elegans in the Coal Measures 



of Staffordshire recorded by Mr Thomas, Dr Kidston has pubUshed 



an account of some specimens from the same district under the 



name Whittleseya {"i.) fertilis^: these consist of smaller cuneate 



scale-leaves or leaflets 1 4 — 2-4 cm. long and 8 — 9 mm. broad ; 



the lamina has a dentate upper margin and is longitudinally 



ribbed. The scales occur in superposed pairs, closely fitting but 



not organically connected, at least in the state in which they are 



preserved; each pair forms a sporangium-Uke case enclosing 



numerous spores but the actual sporangia or synangia have not 



been preserved. Kidston describes the spores as 210 — 222;u, in 



length, elUptical, and characterised in many cases by an oval 



sht; they are practically identical with the microspores of W. 



elegans. 



t 



1 Page 111. ' White (01) p. 108. 



3 Ibid. p. 104, PI. vn. figs. 3, 3a. * Matthew (10). 



* Stopes (14) p. 78. " Kidston (14) p. 166, PI. xv. figs. 1—10. 



9—2 



