ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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filaments, comparable with the plant figured by Kiitzing {Tab. Phyc . 
IV. t. 98) as Gongrosira cMchotoma (which Stahl claims as a develop- 
mental stage of V. geminata). These segments or articulations are 
potential sporangia ; when placed in water, if young they grow out in 
any direction each as a vegetative filament, but if old they liberate 
their spore-contents. The mode of sporogenesis, the mechanism of 
spore-discharge, the morphology of the spores, their amoeboid movements, 
their coming to rest, and their germination after a few days are all 
described. This mode of reproduction occurs in aerial plants only. 
A. G. 
Notes on Charophytes.— G. R. Bullock- Webster ( Journ . of Bot., 
1922, 60 , 148-9). Records of new British localities for some rare 
Characeae. Tolypella nidifica and Ghara canescens have been found in 
brackish water in Orkney. The former was known from one locality 
only, Wexford. G. canescens is a parthenogenetic species, the male 
plant never having been detected in this country, and rarely elsewhere. 
Nitella batrachosperma, the smallest of the British Charophytes, grows 
in deep water, and is probably less rare than it appears to be. N. spanio- 
clema , a recently described species from Ireland, has now been collected 
in Perthshire. A. 0. 
Charophyta of New Caledonia. — James Groves {Journ. Linn. Soc. 
Bot., 1922, 46 , 69-70, 1 pi.). Four species of Nitella and two of Ghara 
collected by R. H. Compton in New Caledonia in 1914. Nitella 
Comptonii is new to science, and is described and figured. A. G. 
Preliminary Notes on the Development of the Carpospores of 
Porphyra tenera Kjellm. — K. Okamura, K. Onda, and M. Higashi 
{Bot. Mag. Tokyo, 1920, 34 , 131-5, 1 pi.). A criticism of Prof. Yendo’s 
paper on the subject {op. cit ., 1919, 33 , p. 73). The authors describe 
their own cultures of P. tenera grown in various media. Spores liberated 
from the margins of fruiting pieces of the alga took at first an amoeboid 
alternation of form, and soon after became roundish. After two to three 
days many of the spores began to germinate by throwing out a small 
process, which gradually elongated, and after about nineteen days had 
developed into a slender, occasionally branched, segmented filament. 
Sometimes two or three filaments were emitted from one spore. The 
cell-contents varied acording to the nutrition, but the distal end of the 
filament was always colourless. The authors regard these filaments as 
rhizoidal, and emitted in order to absorb the necessary nutrition ; though 
they may also have the character of protonema. In one case a sporeling 
had developed as a branch of a rhizoidal filament. Carpospores of 
P. suborbiculata under culture developed in ten days into young fronds 
having long colourless root fibres. The form of the sporeling in 
P. tenera differs from that of P. orbiculata. As regards the long 
rhizoidal filaments, which have disappeared in the other plant, and 
given place to holdfasts, the authors believe that they became atrophied. 
It appears to depend on the degree of maturity of the carpospores 
whether they remain in a non-divided or sparingly divided state, or 
whether they soon develop into young sporelings. The contents of 
immature and mature carpospores are different. The immature carpo- 
