Seed-like Fructification in certain Palaeozoic Lycopods. 309 



men the ligule is clearly shown, enclosed by the integument, the only 

 example of this organ, so far observed, in the mature, seed-like stage 

 of the fructification. 



Another of the Burntisland specimens is the only one as yet 

 observed in which the prothallus is present.* It fills a great part of 

 the functional megaspore, which is almost co-extensive with the spo- 

 rangial cavity, and consists of a large-celled tissue, resembling the pro- 

 thallus of Isoetes or Selaginella. The peripheral prothallial cells are 

 smaller than the rest, but no archegonia could be detected. 



The bodies described in this note resemble true seeds in the posses- 

 sion of a testa or integument, and in the fact that one megaspore or 

 embryo-sac alone came to perfection ; the seed-like organ was likewise 

 shed entire, and appears to have been indehiscent. In many points of 

 detail, however, the reproductive bodies in question differ from the 

 seeds of any known Gymnosperms ; they afford no proof of the origin 

 of the latter Class from the Lycopods. The newly discovered fructifi- 

 cation nevertheless shows that certain Palaeozoic Lycopods, with strobili 

 at first indistinguishable from Lepidostrobus, crossed the boundary line 

 which we are accustomed to draw between Sporophyta and Sper- 

 mophyta. 



As these fossils appear worthy of generic rank, I propose to found 

 the genus Lepidocarpon for their reception; it may be briefly 

 characterized as follows : 



Lepidocarpon, gen. nov. Strobilus, with the characters of Lepidostro- 

 bus, but microsporangia and megasporangia each surrounded by an 

 integument, growing up from the upper surface of the sporophyll. 

 Megasporangium completely enclosed in the integument, except for a 

 slit-like micropyle along the top. A single functional megaspore 

 developed in each megasporangium. Sporophyll, together with the 

 integumented megasporangium, detached entire from the strobilus, the 

 whole forming a closed, seed-like, reproductive body. 



It is proposed to name the Coal-measure form Lepidocarpon Lomaxi, 

 and that from Burntisland L. Wildianum. Both were included by 

 Williamson under his Cardiocarpon anomalum, which, however, is quite 

 different from the seed so named by Carruthers. 



A full, illustrated account of these fossils is in preparation, and will 

 shortly be submitted to the Royal Society. 



* I have since examined a section, cut by Mr. Lomax from one of the Coal- 

 measure specimens, in whicli the prothallus is eren better preserved. Note, added 

 October 9, 1900. 



VOL. LXVII. 



