344 Puget Sound Marine Sta. Pub. Vol. 1, No. 29 



Group 1. Species reproducing both sexually and asexually all winter: 



Agardhiella tenera, Gigartina mamillosa, Gigartina radula exasperata, 

 Gracilaria confervoides, Iridaea laminariodies, Nitophyllum latissi- 

 mum, Polysiphonia californica, Polysiphonia urceolata^ Rhodomela 

 larix, Cryptosiphonia woodii, Prionitis lyallii. 



Group 2. Tetrasporic and vegetative plants: 



Antithamnion floccosum pacificum, Ceramium strictum, Sarcophyllis 

 californica. 



Group 3. Carposporic and vegetative plants: 



Odonthalia aleutica, Callophyllis variegata. 



Group 4. Antheridial plants : 



Antithamnion floccosum pacificum, Dasyopsis plumosa, Odonthalia 

 aleutica, Polysiphonia californica, Rhodomela larix. 



Group 5. Vegetative plants only: 



Rhodymenia palmata, Ceramium californicum. Ceramium rubrum. Con- 

 stantinea sitchensis, Farlowia mollis, Fauchea gardneri. Microcladia 

 californica, Plocamium coccineum, Porphyra perforata, Pterosiphonia 

 baileyi, Rhodymenia pertusa. 



Group 6. Species found too rarely to classify: 



Callithamnion sp., Centroceros sp., Laurencia pinnatifida, Platj'tham- 

 nion heteromorphum typicum, Pterosiphonia dendroidea, Rhodomela 

 lycopodioides. 



It is probable that those in groups (2) and (3) might have been placed 

 in group (1) had there been a greater number of specimens available for 

 examination. For instance, in the case of Antithamnion in groups (2) and 

 (4), in which tetraspores and antheridia were found, it seems improbable 

 that oogonia were not also produced at this season. It is also probable 

 that Odonthalia aleutica and Callophyllis variegata might be found with 

 tetraspores, although it is true that a considerable number of plants of the 

 former were examined without finding any tetrasporic ones. The small 

 number of antheridial plants found indicates merely that the male plants 

 are rare. Groups 1 to 6 above show that the majority of the plants which 

 thrive in winter produce spores in winter, but it also shows that some 

 (group 5) do not. Evidently the colder weather, while permitting vegeta- 

 tive growth, is not conducive to reproduction in some of the winter species. 



The spores of a large proportion of species either germinate in winter, 

 or else produce young sporelings which remain quiescent and are found 

 in considerable numbers during the coldest months. This may be either 

 evidence of the lack of an inhibiting factor so that spores can germinate at 

 any time, or of the presence of an inhibiting factor that prevents the 

 maturing of the sporelings until a later season. Growth records of indi- 

 vidual plants should be taken to show which is the case. 



