190 Geo. K. Sutherland. 
Hypoderma Laminarije nov. sp. (Fig. 3, /—5). 1 
Perithecia in areis rotundis gregatia, immersa, longo elliptica, 
apicibus aliquid praeacutis, 150-200/x longa, circa 130/x lata, scissuris 
longis aperientia, parte superiori atra, carbonacea, basi submem- 
branacea, pallide brunnea ; asci clavati apice attenuato, 69-90/x x 
12*5-14/x octospori; parapbyses filiformes, extremibus leviter inflexis 
vel dilatis; sporidia disticha, fusiformia vel ovoidea 20-25/x x 5-7‘5/x 
primo hyalina, demum parum flavescentia, 1-septata, leviter 
constricta. 
Hab. In thallo vivo Laminariae saccharinae, Orkney. 
This fungus is a decided parasite found extensively along the 
shores of the Orkneys, attacking the stipes of Laminaria saccliarina 
and frequently doing considerable damage to them. As their zone 
is not exposed by the average tide, the ravages of the parasite can 
be seen only either from a boat, or on the rare occasions, when 
exceptionally low tides permit the investigator to walk almost dry 
shod through the Laminaria jungle. Along the narrow and often 
shelving “ sounds ” between the islands an easterly wind acting 
in conjunction with a spring tide lays bare long stretches teeming 
with rarely uncovered animal and plant life. For several years 
the writer has had many opportunities of examining thousands of 
plants in situ and of collecting abundant material. However, as 
they are broken loose and cast up by every storm, it is always 
possible to find infected specimens caught in rock pool or strewn 
along the beach. 
The first appearance of attack is marked by a slight local 
browning which extends its margin rapidly, forming circular or 
irregular, oblong patches, as in Fig. 3, 7. The brown gives place 
to black and later the margins merge into one another, so that 
entire portions of the stalks become discoloured. These are so 
conspicuous on fresh, moist thalli that they can hardly escape 
notice. 
Sectioning reveals the presence of a strongly developed, irregular 
dark-coloured mycelium radiating outward from the points of 
attack. Some of the younger branches are quite hyaline, but the 
characteristic brown is soon assumed. The cells vary in thickness 
from 3-12/x. While some hyphse extend laterally, others are sent 
1 A very brief preliminary note, embracing the diagnostic and more 
obvious characters of this species was appended to a recent account of the new 
genera Trailia and Orcadia (Trans. Brit. Myc. Soc., Vol. 5, 1914) ; the fuller 
description of development and structure were reserved until further observa¬ 
tions were completed. 
