322 
ration in this study allows the conjecture 
that they may be readily adaptable to methods 
of culture, iodine uptake, plant metabolism, 
and tracer studies. 
A listing of algae which gave negative 
tests for iodine is presented here. These spe- 
cies represent approximately 50 per cent of 
all organisms tested. The source of the sam- 
ples is as indicated in Table 1. 
LIST OF SPECIES YIELDING NEGATIVE 
IODINE CONTENT 
Cyanophyta 
Calothrix confervicola (Roth) Ag. ex. Born. 
& Flah M 
Lynghya majuscula "(DiHwyn) Harvey ex. 
Gomot” H 
Chlorophyta 
Boodlea composita (Harvey) Brand H 
Caulerpa crassi folia (C. Ag.) J. Ag B 
Caulerpa peltata (Turner) Lamour B 
Caulerpa racemosa var. laetevirens (Mont.) 
Weber- van Bosse B 
Caulerpa sertularioides (Gmelin) Howe . . . B 
Caulerpa verticillata ] , Ag B 
Caulerpa webbiana Mont H 
Chaetomorpha antennina (Bory) Kuetz. . . . H 
Cladophora sp H 
Cladophoropsis membranacea (C. Ag.) 
B0rg B 
Codium decorticatum (Woodw.) Howe. . . .B 
Codium fragile (Suringar) Hariot O 
Cympolia barbata (L.) Lamour B 
Enteromorpha dathrata (Roth) Grev O 
Enteromorpha intestinalis (L.) Link O 
Enteromorpha linza var. flexicaulis Doty . . O 
Halimeda disco idea Decaisne H 
Monostroma grevillei (Thuret) Wittr . O 
Spongomorpha coalita (Rupr.) Collins . . . . O 
Udotea flabellum (Ellis & Solander) Howe . B 
Ulva angusta Setch. & Gard O 
diva fasciata Delile H 
B 
Ulva lactuca L M 
H 
diva lobata (Kuetz.) Setch. & Gard O 
Urospora penicilliformis (Roth) Aresch. . . . O 
PACIFIC SCIENCE, Vol. VI, October, 1952 
Vaucheria thuretii Woronin O 
Phaeophyta 
Aegira virescens (Carm.) Setch. & Gard.. .M 
Colpomenia sinuosa (Roth) Derbes & So- 
lier B 
Costaria mertensii]. Ag O 
Dictyopteris delicatula Lamour B 
Dictyopteris justii Lamour B 
Dictyota dentata Lamour B 
Dictyota divaricata Lamour . B 
Dilophus guineensis (Kuetz.) J. Ag B 
Ectocarpus indicus Sonder . . . H 
Egregia menziesii (Turner) Aresch O 
Heterochordaria abietina (Rupr.) Setch. & 
Gard O 
Hydroclathrus clathratus (Bory) Howe . . . . B 
Ilea fascia (Mueller) Fries O 
M 
Leathesia difformis (L.) Aresch M 
O 
Padina commersonii Bory H 
Padina pavonia (L.) Gaillon B 
Padina sanctae-crucis B0rg B 
Pocockiella variegata (Lamour.) Papenfuss . B 
Punctaria lati folia Grev M 
Scytosiphon lomentaria (Lyngbye) J. Ag. . . O 
M 
Spatoglossum schroederi (Mertens) J. Ag. . .B 
Zonaria zonalis (Lamour.) Howe B 
Rhodophyta 
Acanthophora spicifera (Vahl) B0rg. B 
Agardhiella tenera (J. Ag.) Schmitz. . . .M 
Bangia vermicularis Harvey O 
Callophyllis crenulata Setch O 
Callophyllis megalocarpa Setch. & Gard. . . O 
Ceramium pacificum (Collins) Kylin O 
Ceramium rubrum (Hudson) C. Ag O 
Ceramium tenuissimum (Lyngbye) J. Ag. . .H 
Champia parvula (C. Ag.) Harvey ...... M 
Chrondrus crispus (L.) Stackh M 
Chrondia sedi folia Harvey M 
Constantinea simplex Setch O 
Cumagloia andersonii (Farlow) Setch. 
Gard O 
Delesseria decipiens J. Ag O 
Dilsea californica (J. Ag.) Schmitz O 
Dumontia incrassata (Mueller) Lamour. . . M 
