the asymmetrical spore is toward the anterior end of the 
seed. The megaspore membrane has a characteristic fi- 
brous texture. 
Schopf compared Lepidocarpon corticosum with Can- 
theliophorus Bassler (Bot. Gaz. Vol. 68, pp. 73-108, 1919) 
and concluded that most, if not all, of the fertile sporo- 
phylls attributed to Cantheliophorus should be transferred 
to Lepidocarpon. However, inasmuch as a number of 
sporophylls of the Cantheliophorus ty pe as well as sporan- 
gia of the Lepidocystis type (White 14) bear many mega- 
spores of the familiar ‘‘Triletes’’ type, it is not possible 
to accept these transfers until a critical revision of all of 
the species has been made. 
The seed megaspore of Lepidocarpon has been named 
Cystosporites by Schopf (12) and he finds it to be a very 
persistent and abundant form among the microfossils of 
certain coals of Illinois. The spore is always rather ovoid, 
elongate and sac-like, varying in its greatest length up 
to nearly 10 mm. The spore membrane has a character- 
istic fibrous construction which is densely matted and is 
thicker and more dense at the distal end. Frequently 
there are abortive spores which for a time remain attached 
to the apex of the fertile member and are appressed to 
the triradiate crest of the functional spore. ‘These abor- 
tive spores become detached as the seed megaspore en- 
larges. They vary greatly in size and when still small are 
nearly spherical in shape. 
One may question the propriety of bestowing a generic 
name upon isolated spores which are referable to some 
plant already possessing a generic name. There is no 
convincing reply to this question. From a botanical and 
nomenclatorial point of view there would seem to be no 
justification for a new generic name, but on the other 
hand,in investigations on the microfossil content of coals, 
one is dealing exclusively with isolated objects for which 
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