222 The Botanical Gazette. [April, 
has stiffish, strongly curved leaves, rather dark green in color, 
4to6 inches long. The crown measures one-half to one 
inchin diameter. The macrospores are 0.51 to 0.55" thick, 
marked with somewhat crested warts, higher and more con- 
fluent into twisted ridges than in the Wicomico plants. The 
microspores are 0.026 to 0.028™" long. The velum is narrow. 
The sporangium is 6 to 7™ in length, very long and slim 
The microsporangium has much the same shape as in /. Ew 
gelmanni var. valida. This form was plentifully planted in 
rather coarse gravel, overlaid with a shallow mud. 
Close beside, in densely compacted masses, grew the set- 
ond form. The leaves are about the same darkish green, § 
to 9 inches long, and remarkable for the number and size of 
their stomata. These leaves spread less widely than in the 
form next preceding. The crown is about one-half inch in 
diameter. The macrospores are 0.51 to 0.53” thick, with 
warts quite crowded and confluent into twisted ridges below, 
sometimes a little reticulated; above, the ridges are some 
what parallel; and in general the markings may be said to dif- 
fer markedly, in both these Lloyd’s creek forms, from the tyPé 
Microspores are 0.024 to 0.032" long. The sporangia a’® 
about 7™" long when longest. The velum is narrow. 
In color, size of sporangium, and general outward aspect 
the two Lloyd’s creek forms vary in a notable manner from the 
Isoetes Saccharata type of Engelmann. This variation is 
the direction of J. riparia as it presents itself in the plants 
collected at Pennsgrove, N. J. and above described. The 
macrospores are of an approximately equal size. But hens 
the resemblance ends; for the macrospores of the Pennsgrove 
plants are, as stated, quite peculiarly deeply ridged, eve? ' 
—— the velum is unusually broad; the habit 1s dioe- 
On the other hand, the small forms of /. riparia noted 
above, from Chester, Pa., vary in spore characters toward the 
Lloyd’s creek plants, to such an extent that if such charac 
ters alone could settle the question, the two would have to be 
classed together. Yet here, as is the former case, the velum 
's often broader than in any known form of J. sacchar am d 
My study of these two species is as yet incomplete, 4 
final conclusions as to their relations are scarcely perms! 
The foregoing notes must make it evident that distinct!” 
structural characters are less numerous even than wou 
