26 CARL SKOTTSBERG, MARINE ALGiE 1. PHJEOPHYCEiE. 



Leathesia (Gray) J. Ag. 



L. difformis (L.) Aresch. 



On Ruppia filifolia in brackish water. Patagonia: Fitzroy Channel, Los 

 Amigos, drifted (S. 17 b, 19. 4. 08, gt.); Skyring Water, near Mina Magdalena, 

 5—6 m (St, 22, 29. 4. 08, gt.). 



I have seen specimens from Sweden, Heligoland, California and the Cape: a 

 comparison shows that all belong to the same species, and I am unable to separate 

 the Patagonian plant from the others. 



Distribution: N. Atl. Ocean, Pacif. coast of N. Amer., Japan, Cape of Good 

 Hope, S. Patagonia. 



Chordaria (Ag.) Rke 



Cli. ftagelliformis (Muell.) Ag. forma: an = Ch. hippuriodeg Bory, Voy. Coquille p. 159? 



S. Patagonia: Straits of Magellan, Susanna Cove, 15—18 m (May 08, sp., 

 leg. A. Pagels); Otway Water, Puerto Toro, drifted (St. 16 b, 15. 4. 08, sp.); Canal 

 Fitzroy, Los Amigos, drifted (St. 17 b, 19. 4. 08, sp.); Skyring Water, Puerto Alta- 

 mirano, on Mytilus, 1—2 dm (St. 18, 22. 4. 08, sp.). 



At first I was inclined to regard my material as representing t w o species, 

 one hardly separable from Ch. flagelliformis, one stouter with larger sporangia, 

 possibly identical with Ch. hippuroides. A comparison gave the following results: 



Locality Salinity Length of Sporangia Assimilators 



St. 18 Brackish water 30—60 jj. 00 — 90 [i. 

 St. 17 b Less brackish tlian 



St. 18 60 [i. 90 [t. 



St. 16 b Water more salt 60—85 ;j. 90—105 \i. 



Susartna Cove Water quite salt 90 ;). 120 ;j. 



There seems to be a relation between the salinity of the water and the size 

 of sporangia and assimilators. The salt water plants from the Magellan Straits are 

 decidedly coarser and have larger sporangia and longer assimilators than the Chor- 

 daria growing at Heligoland, where I studied these plants. If this is a character 

 of importance, the southern form might be regarded as a good species; I guess this 

 is what Bory described as Ch. hippuroides, but his diagnose is very incomplete. At 

 present it is better to leave it under Ch. flagelliformis, to which species Hariot, 

 Miss. sci. Cap Horn, referred the Magellanic plant. 



Cotton, Crypt. Falkl, p. 169 records Ch. capensis Kutz. from the Falklands, 

 collected by Vallentin and Hennis. He says that »the five specimens brought 

 ho me by Mrs. Vallentin agree with the Cape species rather than with C. flagelli- 

 formis, and it is probable that all the records of the latter from Fuegia refer to 

 this species». 



In 1907, I recorded Ch. capensis from Fuegia, and I did not collect anything 

 like Ch. flagellaris during the Antarctic Voyage. 1 have no reason to doubt the 





