52 M. FOSLIE. [1905 



thothamnia from Greenland for examination. I separated 1. c. from 

 the said species a form which I referred to L. flabellatum f. Granii, 

 and which bore sporangia two-parted. The other specimens, which 

 were in habit quite like forms of L. soriferum Kjellm, were partly 

 sterile, and partly they were not closer examined. They were 

 referred to L. tophi forme, in the sense then taken, though much 

 approaching f. Granii. Be it said that in Norw. Lithoth. I pre- 

 sumed that, in forms with sporangia partly two-parted, partly four- 

 parted, apparently belonging to the same species, the former were 

 not fully developed. Cp. L. norvegicum f. saxatilis and other 

 species 1. c. It is, however, sometimes difficult to decide whether 

 a specimen bears two-parted sporangia or in fact four-parted ones, 

 as in the latter case the middle wall may seem to be fully, or 

 almost fully, developed before the other two walls are founded or 

 visible. Cp. Norw. Lithoth. p. 6. Having anew gone over a part 

 of the said material from Greenland, I have not succeeded in 

 finding any specimen with sporangia four-parted, but several spe- 

 cimens with only two-parted ones. At the same time, I have also, 

 among the considerable material more recently collected at the 

 coast of Norway, found a form bearing sporangia two-parted 

 which resembles L. soriferum, viz. L. tophiforme in the sense 

 here taken. It even appears to be much more widely distributed 

 than L. soriferum. 



On the other hand, it is still rather doubtful to me what im- 

 portance ought to be attached to the parting of the sporangia, or 

 whether the said parting is on the whole to be looked upon as 

 a character of species. . L. tophiforme and L. soriferum are not 

 growing gregariously in the same locality. In one locality I have 

 only found one species, and in another place only the other, i. e. 

 specimens with sporangia two-parted or specimens with sporangia 

 four-parted, respectively. In one case, however, I have found 

 both four-parted ones and two-parted ones apparently fully deve- 

 loped even in one and the same specimen, in a place where coarse 

 forms of these species were growing together with L. glaciale. 

 Cp. below. 



