XXXV] CARPOLITHUS 365 



there are several examples of both large and small types without 

 any regular ribs or lacking such features as serve to distinguish 

 the genera already described, which are appropriately included 

 in Carpolithus. The two species Carfoliihus Wildii Kidst.^ and 

 C. bivalvis Goepp.* are two examples of seeds from Upper Carboni- 

 ferous rocks which it is desirable to refer to this comprehensive 

 genus pending further discoveries as to their morphological 

 features. The Jurassic species C. conicus Lind. and Hutt.^ is 

 another type which it has been customary to include in Ca/rpolithus. 



(Microspermum. Arber.) 



The generic name Microspermum has recently been proposed 

 by Arber* for some WestphaUan seeds described by Carpentier^ 

 from the North of France as Carpolithes'i samaroides and for 

 similar fossils from the Middle Coal Measures of Nottingham. 

 The supposed seeds are small, ovate or pyriform bodies, 5 — 12 mm. 

 long and 2-5 — 6 mm. broad, with one extremity broadly rounded 

 and the other acute: one side is keeled, the other grooved, and 

 a large foramen occurs near the broader end and on the grooved 

 surface. Arber emphasises the fact that the specimens are sym- 

 metrical in one plane only. As the author of the genus points 

 out the morphological nature of the fossils is not thoroughly 

 estabhshed, nor is the parent-plant known. In view of the ill- 

 defined characters of the specimens so far discovered it is hardly 

 desirable to institute a new generic name implying their seed- 

 nature ; moreover Microspermum has previously been employed for 

 a genus of Compositae. An examination of specimens leads me 

 to doubt their seed-nature and it would seem more likely that 

 they are foUar organs, possibly bracts which originally bore seeds 

 or sporangia. 



An examination of some of the specimens of supposed Permian 

 seeds for which Geinitz® proposed the generic name Guilelmites 

 convinced me that they are inorganic structures, probably nodules 

 in shale smoothed and rounded by shckensiding. 



1 Kidston (92) p. 8; Arber (14) PI. vii. fig. 28. 



2 Kidston (86*) B. PI. m. figs. 7 a— c; Berger (48) PI. ii. figs. 30, 31. 



3 See poslea. * Arber (14) pp. 90, 100, PI. vn. figs. 22—27. 

 ^ Carpentier (11) p. 7, PI. xiv. fig. 3. 



8 Geinitz (62) p. 145, PI. xxv. figs, 7—9; Goeppert (64) A. p. 145. 



