l66 
William J. Hodgetts. 
species of Ulothrix growing in nature—under widely different 
geographical conditions, it seems best to keep Uronema as a 
separate genus. 
Moreover, Brand 1 has brought forward weighty evidence 
tending to prove that the pointed appearance of the end-cells of 
Hormidium flaccidum A.Br. observed by Gaidukov is simply due 
to remnants of shrivelled up intercalary cells which sometimes 
persist on the terminal cells of broken-up lengths of the filaments. 
It is quite possible, however, that a wider knowledge of 
Uronema may show it to be a little more than a sub-genus of 
Ulothrix; and in this connection it is interesting to note that 
U. elongatum, in the length of its filaments, recalls the habit of a 
Ulothrix much more than do either of the other two species of 
the genus. 
The following is a diagnosis of the new Uronema : 
URONEMA ELONGATUM sp. n. U. filis haud ramosis, 
rectis, rarius leviter incurvis, usque ad 5 mm. longis; cellulis 
basali apicalique exclusis exacte cylindraceis, rarius leviter turgidis, 
diametro 4-13 (plerumque 5-9) -plo longioribus; cellula apicali 
sursum acuminata, at in pilum hand attenuata, plerumque 
leviter turgida et plus minusve curvata, at interdum tota 
rectissima ; cellula basali attenuata, pulvino parvo mucoso affixa ; 
chromatophoro parietali, mediano, (-f) longitudinis cellulae 
complente, pyrenoidibus 1-3 (plerumque 2) prtedito. 
Propagatio macrozoogonidiis, singulis in quaque cellula 
oriundis, ciliis 4 instructis, per ostium poriforme cellulae matricalis 
evadentibus. 
Long. cell. (cell. bas. exc.) 22—80 (plerumque 28—56)/*; 
lat. cel. 4*4—9’6 (plerumque 5—7*5)yu.; 
long. cell, basal. 60—90/*. 
Hab. in stagno parvulo, King’s Norton, Birmingham, in 
Oedogonii sp. et plantis phanerogamis aquaticis ( Myriophyllo, 
Lemnce minoris radicibus) epiphyticum; etiam in stagno, Victoria 
Park, Dudley Port, Staffs, in Cladophora glomerata. 
In conclusion I wish to express my thanks to Prof. G. S. West 
for very kindly examining the alga for me, and also to Mr. W. B. 
Grove, M.A., for his kind help in connection with the literature. 
1 Brand, Ber. Deutsch. Bot. Ges., Vol. XXXI, 1913, p. 69. 
