525 
in diameter; oogonia clustered, oospore 272 to 306:long, 170 to 
240 broad; surface too immature to examine. This plant occurs 
very sparingly among the collections of number 8, which I have 
received ; it is probably a reduced form of that species ; its extreme 
delicacy is shown by the measurements of stem and leaves. 
These forms 7, 8 and 9 belong to the section Polyglochin or diar- 
throdactylae — brachydactylae — subdivision of Mitella. The 
Sogonia being clustered (not isolated at the nodes of the leaf) 
place the species near the three American sub-species, microcarpa 
A Br., Glaziovit Zell, and megacarpa Allen, alf doubtless forms of 
One species for which sicrocarpa, the oldest name, is very inappro- 
priate. These species as well as o/igospiva possess oospores with 
a reticulated membrane, quite distinct from WV. orientalis Allen ; in- 
deed XV. Japonica Allen is to be included in this group, it was er- 
roneously referred by me to the ofigospira section, but later col- 
lections show distinctly clustered oogonia ; the cells of the coronula 
are however elongated, placing it in alliance with the true JV. fol- 
Slochin series, which is separated by coronula characteristics from 
Our WV. orientalis, which has a short coronula. [Illustrations of 
these new Japanese species will follow later when a series of eight 
plates can be prepared. 
10. NITELLA PAUCICOSTATA sp. nov. Monarthrodactyla, fur- 
cata, homoeophylla, gymnocarpa, dioica, apiculata, membrane of 
Cospore granulated. (Series of WV. opaca Ag.) 
‘ Plant 2 to 6 inches high, branched from the base, diffuse and 
flaccid. Verticils remote, at length becoming crowded above, 
bearing about eight leaves and usually short peduncles (shoots) 
which fruit abundantly when very short, close to the base of the 
verticils. Leaves once divided, often long and slender (bright 
green and flaccid in our specimens); terminal segments three, 
about as long as the first segment of leaf, abruptly pointed (like | 
N. opaca). Stem 366 to 500 in diameter; leaf first segment 146 
to 425 usually 300 diameter; second segment, 170 to 220 usually 
170 diameter. Fruit clustered at the node of the leaf; oogonia 
2~3, globular; coronula minute, evanescent; oospore about 408 
long by 340 broad (400 by 340, 408 by 380, 440 by 374, 440 by © 
360, 440 by 370); membrane of oospore very minutely roughened; | 
2 ; ridges only 4 (or 5); antheridia 488 in diameter. 
to the multiplying opaca series. In reviewing the species of 
ie 
_ This species was collected near Tokio, and adds another ‘ o 
