XXX] WHITTLESEYA 131 



fertile are microspore-bearing leaflets of Pteridosperms, possibly 

 of some Medullosan plants. The leaflets of Whittleseya agree in 

 form fairly closely with those of Potoniea adiantiformis Zeill. 

 described on a previous page 1 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 2 , characterised 

 by 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 English specimens, that the Whittleseya leaves 

 may be fertile pinnules of a Pteridosperm frond. Among other 

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

 Nova Scotia 3 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 4 has also described a Canadian species 

 W . concinna from New Brunswick in beds assigned by Dr Stopes 5 

 to the Westphalian series. 



Whittleseya Jertilis Kidston. 



Since the discovery of Whittleseya elegans in the Coal Measures 

 of Staffordshire recorded by Mr Thomas, Dr Kidston has published 

 an account of some specimens from the same district under the 

 name Whittleseya (?) fertilis 6 : these consist of smaller cuneate 

 scale-leaves or leaflets 1-4 2-4 cm. long and 8 9mm. 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-like case enclosing 

 numerous spores but the actual sporangia or synangia have not 

 been preserved. Kidston describes the spores as 210 222/z in 

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

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

 elegans. 



1 Page 111. 2 White (01) p. 108. 



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



5 Stopes (14) p. 78. 6 Kidston (14) p. 166, PL xv. figs. 110. 



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