149 



in fact also the case with the other forms. Pl. 17, fig. 7 and 10 

 represents what I apprehend as the typical form, characterized by 

 its subspherical or rather irregular frond, with the branches being 

 partly rather erect partly and more frequently somewhat spreading 

 and seldom straight, but most often rather bent or even curved, 

 on the one side passing into f. globosa and on the other side into 

 f. squarrosa and f. alcicornis. The branches are up to 3 mm. 

 thick, frequently about 2 — 2.5 mm., and the are never so regularly 

 fastigiate as in typical specimens . of f. globosa, often bearing more 

 or less numerous wart-like processes or short branchlets. It gets 

 up to about 12 cm. in diameter, frequently, however, less. 



The form globosa is generally smaller than the preceding, 

 spherical or nearly spherical, and the branches are erect, straight 

 and fastigiate, more densery branched and the branches more 

 seldom bearing wartlike processes. The apices occasionally are 

 truncate or nearly truncate. Cp Contrib. II, pl. 3, flg. 3. 



The form squarrosa is very irregular in shape, in all much 

 varying and little independent, although in its typical development 

 rather differing from f. typica and easily recognized. The branches 

 are much spreading, frequently rather flexuous and curved, less 

 branched than the other forms, and the ultimate most often rather 

 elongated. Pl. 21, fig. 8 — 9. The surface of this form is nearly 

 always quite smooth, which, however, frequently also is due to the 

 other forms, though these are less seldom here and there furnished 

 with scaly thickenings, very seldom nearly over the whole frond. 



As remarked 1. c. L. alcicorne cannot be concidered more 

 than a form of the present species. It is very characteristic in 

 its most extreme form, but far from being independent, and it 

 especially is nearly related to f. typica. Two specimens repre- 

 sented 1. c. pl. 3, fig. 4 plainiy show transitions to this form. 

 Specimens of the last named form, or forms standing between 

 this and f. globosa, often bear hear and there compressed branch- 

 systems, and those separated much resemble small specimens of 

 f. alcicornis. 



The conceptacles of sporangia are quoted by Kjellman 1. 

 c. to be „small, scarcely perceptible to the naked eye", and the 



