xxxvn] CYCADOCEPHALUS 475 



complete investigation of the specimen confirmed the first of 

 these suggestions, but there is no evidence that there was an 

 ovulate receptacle in the centre of the flower. The appendages 

 are attached by a rather broad and slightly cordate base and 

 are represented by a thin carbonised cuticle of rectangular cells 

 showing in one case a row of imperfectly preserved stomata: 

 on this are numerous groups of tetrahedral microspores, about 

 55fji in diameter, which show a more or less well marked arrange- 

 ment in rows transverse to the long axis of the thin laminae. 

 It is clear from Nathorst's researches that the groups were enclosed 

 in loculi bounded by thin-walled cells 1 , the loculi being in trans- 

 verse rows on each side of a midrib. Nathorst speaks of the 

 appendages as synangia characterised by the large number of 

 the sporogenous compartments, and he compares them especially 

 to the fertile leaflets of Danaea elliptica as described by Bower 2 , 

 each appendage being comparable with a revolute Danaea pinnule 

 in which the edges of the lamina are united. This is illus- 

 trated by the section of an appendage (fig. 574, D) reproduced 

 from Nathorst's restoration of a Cycadocephalus microsporophyll. 

 From a morphological point of view it would seem more appro- 

 priate to speak of the appendages as highly modified pinnules 

 rather than synangia. The second species, C. minor, agrees 

 closely except in its smaller size with the type-species. Nathorst 

 regards Cycadocephalus as a unisexual flower differing from those 

 of Williamsonia and from the microsporophyll-verticils of Cyca- 

 deoidea in the structure of the synangia and in the tetrahedral 

 form of the spores, though the latter feature he considers to be of 

 secondary importance, as both bilateral and radial spores occur 

 in recent Marattiaceae. He includes the genus in the Bennetti- 

 tales but suggests that it should be referred to a separate family 

 as an indication of the possession of characters which mark it 

 off from Williamsonia, Weltrichia, Wielandiella, and Cycadeoidea. 



WELTRICHIA. Braun. 



The name Weltrichia was given by Braun 3 to some Rhaetic 

 fossils discovered by Weltrich near Culmbach in Franconia which 



1 See the photographs reproduced in Nathorst's latest and most complete 

 account (12 2 ). 



2 Bower (97) B. 3 Braun (49). (I have not seen this paper.) 



