2 Howe: MONOSPORANGIAL DISCS IN LIAGORA 
procarps, or the subsequent cystocarps may nearly always be 
found, but the writer in examining some hundreds of specimens, 
has never seen anything that could be certainly interpreted as 
tetrasporangia or as a non-sexual alternating generation. In the 
older systematic works, it is either expressly stated that tetra- 
spores in the genus Liagora are unknown or else silence is main- 
tained on this point. In Schmitz’s treatment of the genus in 
Engler & Prantl, Die natiirlichen Pflanzenfamilien, we find, 
‘“‘Sporangien ungeniigend bekannt, angeblich an knotig ver- 
dickten Stellen der oberen Thalluszweige aus den Endzellen der 
Rindfaden entwickelt und unregelmassig paarig geteilt.” De- 
Toni, in his Sylloge Algarum, appears to have carried this state- 
ment over into Latin, omitting, however, to translate the “ange- 
blich.””. Whether this statement by Schmitz rests upon his own 
personal observations or is based upon some previously published 
observation that has escaped the attention of the present writer 
is not clear. Oltmanns, in his Morphologie und Biologie der 
Algen, is apparently silent in regard to this matter. 
In Kiitzing’s Tabulae Phycologicae (8: 43. pl. 90 I. 1858) we 
find in his delineations of Liagora Turneri from the Red Sea a 
figure showing ‘‘Ein Gliederfaden, dessen eine Zelle sich zu einer 
Brutzelle erweitert, aus welcher sich die in d. e. f. g. h. i. dargestell- 
ten Knospen entwickeln, welche der Anfang der Seitensprossen 
sind.” Structures evidently similar to those figured by Kiitzing 
occur in at least four of the West Indian species of Liagora (L. 
ceranoides, L. valida, L. farinosa, and L. pinnata), which often 
show small flat orbicular discs lying on the general surface of the 
plant or somewhat immersed among the assimilatory filaments. 
These discs are of a deeper red color than the main Liagora plant, 
they send down few or numerous roothairs from their ventral 
- (proximal) surface in among the assimilatory filaments, and they 
bear on their dorsal (distal) surface a few sporangia, the contents 
of which remain undivided, so that they may referred to as MON” 
sporangia. Long, colorless, gelatinizing hairs may usually - 
seen, arising from this outer or dorsal surface. The disc is "¥ 
volved in mucus, the outer limits of which may be distinct or M4Y 
be vague or imperceptible. Except in the youngest parts of . 
Liagora, this mucous envelope is more or less calcified. These 
