270 PERCY SLADEN TRUST EXPEDITION 
Amongst the alge of the Indian Ocean J found species of two new genera, Tapeino- 
dasya and Oligocladus, described for the first time from the Malay Archipelago in ‘‘ Les 
Annales du Jardin botanique de Buitenzorg,” vol.ix.1910. It afforded me great pleasure 
to describe these species, which confirm the validity of my new genera. One genus, 
Pseudendosiphonia, is new in the present collection; it is most closely allied to Hndo- 
siphonia, and yet is so different that it can be easily distinguished ; one species, Dasya 
indica, had to be described as a new genus—Amphisbetema. 
Many of the algze are barren, and can therefore not be specifically named; others are 
only fragments. I have given the generic names of all, because I think that, for our 
knowledge of the geographical distribution, even a generic name may have some value. 
The collection is rich in novelties; I often hesitated before describing a given alga as 
new, but when, after careful investigation, I could not -identify it with any existing 
diagnosis, I felt I had no alternative. Of the novelties, which include one genus, 
17 species, one variety and one form, 11 are from deep water, 2 from reef and deep 
water, 7 from reef alone. It may be well to recall here that Mr. and Mrs. Gepp 
found Avraimvillea amadelpha in material from reef and deep water. Many algze appear 
to accommodate themselves to both modes of living. The ‘“Sealark” Expedition had, 
like the ‘“ Siboga” Expedition, the advantage of the use of a dredge, and several hauls 
from deep water, where many Rhodophycez flourish, have given a rich harvest. The 
nature of the bottom surrounding the reefs and islands, whence these algee come, has 
been treated in detail in the above-mentioned paper by Mr. Foslie. I think it therefore 
unnecessary to do this again. 
The geographical distribution shows that a great resemblance exists between the 
algological flora of the Indian Ocean and that of the Malay Archipelago as well as that 
of the east coast of Africa. Of the 26 species found at Mahé and Diego Garcia by the 
“* Deutsche Tiefsee-Expedition,” 7 occur also at Dar-es-Salaam, and of the 8 other 
species collected at Dar-es-Salaam by that expedition 5 are found in the Stanley 
Gardiner collection *. But it is a puzzle to know how Cladhymenia oblongifolia and 
Calliblepharis prolifera, only known hitherto from New Zealand, and Chondria pusilla, 
only known from the West Indies, came to be inhabitants of the present region. It 
emphasizes the fact that the geographical distribution of algze is a factor that should 
always be very carefully considered. The finding of Peyssonnelia Harveyana, known 
only from the Atlantic Ocean at Brest, puzzled me less, because it may be possible that 
the determination of the barren plant is erroneous. I have therefore queried it. 
I have given a list of the localities with the algze found at each, and a general list of 
all the Rhodophycez collected by Mr. Stanley Gardiner. The systematic observations 
on the different genera and species conclude the paper. 
I wish here to express my sincere thanks to Mr. Stanley Gardiner for entrusting me 
with his collection, and to Messrs. Gepp and Cotton for the kind help they have given 
me; and I may perhaps add a word of deep-felt regret that Mrs. Gepp was unabie to do 
her share of the work. 
* The number of species common to both regions is probably far greater, for in the recently published paper by 
Br. Schroder, ‘“* Zellpflanzen von Ost-Afrika,” Hedwigia, Bd. lii., four more species are mentioned, also found in the 
present collection. 
