472 PROCEEDINGS OF THE AMERICAN ACADEMY 



number of specimens of this group which are to be found in herbaria. 

 An extraordinary number of specimens, not fiw from 150, were col- 

 lected at Ungava Bay, and with this large amount of material it may 

 be possible to obtain a better knowledge of the variations of the spe- 

 cies of this group than has hitherto been possible. Some of the mate- 

 rial was mounted, and the rest was kept rough-dried and soaked out by 

 me for examination. The specimens furnished an abundance of tetra- 

 spores, and in some cases cystocarps. Some of them were from six 

 to eight inches long, the fronds arising from a disk-like base as far as 

 could be judged from the small number of specimens in which the base 

 was present. In general the specimens could be arranged in two sets, 

 although transitional forms were unfortunately frequent, and I am al- 

 most forced to believe that they are all forms of a single species, but 

 what to call that species it is not easy to decide. In one set the main 

 axis bears a number of long lateral branches, which are comparatively 

 thin and compressed and more or less regularly zigzag, giving off the 

 short secondary branches at the angles. The ultimate branches are 

 short and distichously pinnate, becoming somewhat corymbose at the 

 tip. There can be little doubt that the specimens just described should 

 be placed in Delesseria corymbosa. The figure of that species in Kjell- 

 man, loc. ciL, Plate X. fig. 3, resembles closely the specimens from 

 Ungava Bay, although the plant figured is somewhat smaller and nar- 

 rower than ours. 



The first set of specimens to which I have referred suggest in habit 

 some of the forms of Microcladia Coulteri, Harv., of our west coast. 

 The fronds of the specimens of the second set are less compressed, 

 and the ultimate branches are more attenuated, so that, in some cases, 

 they resemble somewhat forms of Ceramium ruhrum. The arrange- 

 ment of the cystocarps and tetraspores is the same in both sets of 

 specimens. A small number of specimens similar to those now placed 

 in the second set were collected on kelp in six fathoms, at Annanactu 

 Harbor, by Kumlien, in October, 1877, and were referred by me to 

 Delesseria rostrata, J. G. Ag. A specimen was afterwards examined 

 by Professor Agardh, who thought that it was Del. Baerii rather than 

 Del. rostrata. Certainly the Ungava Bay alga resembles the figure of 

 Del. Baerii in Kiitzing's Tabula Pliycologicre, di-awn from a speci- 

 men in Herb. Sonder, and also a specimen from Nova Zembla col- 

 lected by Kjellman. Del. Baerii., first described from the Arctic 

 Pacific region, extends as far as Spitzbergen, but is not credited to 

 Greenland or the eastern coast of America. Del. rostrata., Ag., 

 based on Lyngbye's Gigartina purpurascens, var. rostrata, is a Green- 



