208 SUMMARY OF CURRENT RESEARCHES RELATING TO 
of the harvesting, without injury to the field of algae ; also (2) the 
application of analytical methods to fresh algae in situ ; the determina- 
tion of the iodine in exact figures ; the comparison of the percentages 
of iodine, ash, tangic acid, reserve hydrocarbons, cellulose, and pig- 
ments. E. S. G. 
Mediterranean Algae. — H. E. Petersen ( Report Danish Oceanogf. 
Exped. (1908-10) to the Mediterranean. Edited by J. Schmidt. 
II. Biology. Copenhagen, 1918, 3, 1-20, 11 .figs.; see also Dot. 
Gentralbl ., 1919, 141, 279). A list of 123 species from 21 Mediterranean 
stations. Only the few dredgings from the Tunis coast and from the 
iEgean Sea yielded any good geographical information. Geramium 
brevizonatum is described as new. Critical remarks and figures are 
appended to several species. About 35 species are recorded for the 
iEgean for the first time. A. G. 
Study of the Algal Associations of San Juan Island. — Walter 
L. C. Muenscher {Puget Sound Marine Station Publications , 1915, I., 
59-84, 6 pis.). The rocky shores of San Juan Island possess a very 
dense algal flora ; but the sandy beaches and bays are almost devoid of 
algae. Four distinct associations are to be noted as one descends from 
high-tide level to the Nereocystis beds — namely, the (1) Endocladia 
association ; (2) Fucus association ; (3) Ulva association ; (4) Lami- 
nariaceae association ; and (5) Zostera association (in the shoal-water of 
bays). The number of species common to each association increases in 
the lower associations, and the algae are larger in the lower associations. 
Bed, brown, and green algae are found in each of the four associations. 
Bhodophyceae are found almost equally distributed in the different 
associations. Phaeophyceae are most abundant in species in the Lami- 
nariaceae association. Chlorophyceae are most abundant in the Ulva 
association. Myxophyceae are represented by only a small number of 
marine species. A. G. 
Ability of Seaweeds to withstand Desiccation. — Walter L. C. 
Muenscher {Puget Sound Marine Station Publications , 1915, 1., 19-23). 
An account of experiments made with thirteen species (here arranged as 
they approximately occur in order of succession, from dry land down 
to low tide line) : — Gloiopeltis furcata , Fucus evanescens, Gigartina 
mamillosa, Golpomenia sinuosa , Rhodomela larix , Porphyra perforata , 
Halosaccion glandiforme, Iridsea laminarioides, Ulva lactuca , Sarcophyllis 
calif ornica, Alaria valida, Desmarestia aculeata, Nereocystis Luetlceana. 
The order is somewhat altered in the table which shows their ability to 
withstand desiccation ; but as a general rule those species which grow 
highest above low tide level can stand the most desiccation, and those 
near the low tide level are the least resistant. It is a question of actual 
resistance to desiccation ; and wave-action is not a factor in the situation 
of the plants. Ability to withstand desiccation may not be the only 
reason why some species grow high above low tide level, but drought is 
certainly one of the causes preventing certain species from growing much 
above low tide level. A. G. 
