only the smaller and more immature forms are recognized 
as typical Lepidocarpon, that is specimens still within an 
integument. All of the seeds attaining the maximal or 
near maximal size are found isolated. 
LeEpPIDOCARPON Scott, Phil. Trans. Roy. Soe. Lond. 
B. vol. 194, 1901. 
Lepidocarpon (Lepidocystis) glabrum Darrah sp. 
nov. 
The seeds are large, 10-16 mm. in length, 8-10 mm. 
in width and 8.5—4.5 mm. in thickness. The seed body 
is smooth and lustrous with no ornamentation present. 
There is asmall pit or interruption in the cells of the in- 
tegument at the base of the seed where the vascular traces 
have entered. The protective integument is the massive 
sporangial wall, which is composed of columnar cells, usu- 
ally filled with a dense substance. Within this integu- 
ment, towards the center, are four tissues which are 
conspicuously different from one another. The outer of 
these is a closely packed tissue composed of rounded, 
nearly isodiametric cells with rather thick walls, larger 
in diameter than the columnar cells on the periphery. 
This tissue is several cells deep. The next tissue is a loose 
network of rounded parenchymatous cells which are, at 
maturity, somewhat larger than the preceding. They have 
thin walls and are frequently irregular in shape. Within 
this tissue is a closely packed mass of smaller, isodiametric 
and thin-walled cells, which line the cavity and complete- 
ly surround the fourth tissue (the gametophyte). The 
seed megaspore is always present. The megaspore is of 
the Cystosporites type; abortive spores occasionally can 
be distinguished. In the basal portion of the seed there is 
a dense pad composed of the second parenchymatous tis- 
sue, into which runs a vascular strand that divides twice 
to form four short strands which soon exhaust them- 
[ 98 | 
