Algae of New Zealand— LlNDAUER 
347 
Fig. 5. Species of Leathesia and Hapalospongidion. 
a-d, Leathesia novae-zelandiae sp. nov. : a, colonies on 
host (X 0.5); h, undersurface (X 2); c, vertical cut 
through long axis of smaller specimen (X 2 ) ; d, 
paraphyses and sporangia (one dehisced) (X 140). 
e-i, Hapalospongidion durvilleae sp. nov.: e, on host 
(X 0.5); f, habit sketch (X 35); g, filament with 
penetrating rhizoids and sporangia (one injured) 
(X 150); h, a sporangium (X 280); i, tips of fila- 
ments ( X 266) . j—l, Hapalospongidion saxigenum 
sp. nov.: j, tips of filaments (X 166); k, base of 
filament (X 166); l, unilocular sporangia (X 170). 
filaments has not yet been satisfactorily deter- 
mined. 
The plants form small, oval patches at first, 
but later these become confluent and cover large 
areas within the margins of the blade of the 
host, not only on one surface of the blade but 
also on the opposite surface, the colony assuming 
exactly the same size and shape of that on the 
opposing surface, as if the parasite had grown 
right through the thallus of its host. The color, 
en masse , is dark brown and velvety but, on 
drying, it becomes yellowish-sienna and is very 
conspicuous on the dark, almost black frond 
of the dry Durvillea. The protoplast is very 
light straw-colored, almost colorless under the 
microscope, but the sporangia are somewhat 
darker and very numerous in a low line among 
the long, erect filaments. This lack of color of 
the protoplast is in accordance with the plant’s 
parasitic state. The chromatophores are small, 
disc-shaped, sparse, except at the tips. 
This species may prove to belong to a new 
genus but in the meantime, until the plant is 
cultured, it is as well to place it here tentatively. 
Distribution: So far known only from Stewart 
Island, the type locality, where it is abundant in 
autumn and winter. 
Type specimen No. 6253, Herbarium Lin- 
dauer; iso-types were distributed in Lindauer 
(1946), Algae Nova-Zelandicae Exsiccatae, 
No. 230, as Herponema? 
Hapalospongidion saxigenum sp. nov. 
Fig. 5 H- 
Thallis minutis, erectis, aggregatis, fulvis, 
lubricis; filis simplicibus, arete clavatis, 225- 
725 p altis, 6-18 p latis, constantibus e cellulis 
ad 60, cacuminibus obtusis, cellulis vix longi- 
oribus quam latioribus, paene tumido-cylindricis 
vel moniliformibus, cellulis basalibus aliquanto 
arctioribus, orthogoniis, ecoloribus, 2-plo longi- 
oribus quam latioribus; chromatophoris minutis, 
disciformibus; unilocularibus sporangiis grandi- 
bus, terminalibus, ovatis vel clavatis, 105-170 p 
altis, 36-45 p latis, parietibus cellularum con- 
spicue crassis, pedicello constante e 12 vel 
pluribus cellulis, superne 12 p latis, infra 4-6 p 
latis; sporangia plurilocularia non cognita. 
Thalli minute, erect, gregarious, dull yellow- 
ish-brown, lubricous; filaments simple, narrowly 
clavate, 225-725 p high and 6-18 p wide, con- 
sisting of up to 60 cells, tips obtuse, cells scarcely 
longer than wide, somewhat barrel-shaped or 
moniliform, basal cells somewhat narrower, 
rectangular, colorless, twice as long as wide; 
chromatophores minute, disciform; unilocular 
sporangia large, terminal, oval or clavate, 105— 
170 p high and 36-45 p wide, with conspicu- 
ously thick cell walls, pedicel of 12 or more 
cells 12 p wide above and 4-6 p wide below; 
