54 PTERIDOSPERMEAE [CH. 



Scott Pteridotheca Butterworthi^ and regarded by him as filicean 

 sporangia that cannot be referred to any known Carboniferous 

 genus. The piece of lamina bearing an empty sporangium, 

 which may or may not have possessed an annulus, reproduced 

 in fig. 407, C, occurs in association with the larger specimen 

 shown in fig. 404, B, and it would seem not unreasonable to 

 regard both as parts of the same frond, namely a frond of Lyginop- 

 teris. As Prof. Weiss^ points out, the accurate determination of 

 small pieces of petrified pinnules is exceedingly difficult and without 

 more decisive evidence we are hardly justified in asserting that 

 the sporangia figured by Chodat and Scott and that shown in 

 fig. 407 belong to the genus Lyginopteris. Although the available 

 data appear to favour the view generally held that Kidston's 

 conclusion is correct additional evidence would be welcome. 



Telangium. Eeference was made in vol. ii.' to the genus 

 Telangium instituted by Dr Benson for some petrified sporangia 

 from the Coal Measures regarded by her as the microsporangia 

 of a Pteridosperm, probably ^ Lygino'pteris. The sporangia of 

 Telangium are similar to those of Crossotheca. Scott points out 

 that they are borne on a flat disc or lamina 'quite comparable 

 to a fertile pinna of Crossotheca*,' and he concludes that these 

 sporangia are not generically distinct from the impressions on 

 which the genus Crossotheca was founded. Kidston* regards 

 Telangium Scotti, Benson, as the microsporangium of a Pteridosperm 

 though not of Lyginopteris, on the ground that the microsporangia 

 described by Miss Benson are not attached to a limb and that 

 they have a single loculus in place of the double loculus (fig. 407, A) 

 of Crossotheca. The presence of a limb in Telangium recognised 

 by Scott removes one of these distinguishing features. There 

 are, however, no adequate reasons for regarding Telangium Scotti 

 as specifically identical with Crossotheca Hoeninghausi. The 

 synangium of Telangium Scotti, 5 mm. in length, consists of 6 — 12 

 sporangia united basally and opening when ripe by longitudinal 

 dehiscence. Fig. 493, E, shows eight sporangia of a synangium in 

 transverse section: the two sporangia at the lower end of the 

 section are less distinct than the others, some are full of spores 



1 Scott (08) B. p. 292. = Weiss, P. E. (12). » Vol. n. p 532 



' Scott (09) B. p. 400. » Kldston (06) B. 



