14 M. FOSLIE. [1899 



The form heterophylla which once was considered by me to 

 form a separate spedes together with the below mentioned f. aga- 

 riciformis is in fact a form of L. Uchenoides. Mediterranean spe- 

 cimens of this form on the one side stands near to f. depressa 

 and, on the other hand, often rather approaching f. agariciformis 

 in habit. However, it is coarser, the lamels larger and not so fra- 

 gile as in the latter. It often has a tendency to develop plain or 

 nearly plain lamels, although they are most frequently to be found 

 more or less rising, curled round into little cups, or irregularly 

 folded. Two lamels trumbling often rise against eaeh other and 

 grow upwards into irregularly folded forms or even double-vvalled 

 cups. Sometimes the lamels are seen to be decussate, ur upon 

 the whole much varying in shape. 



A specimen that I have seen from the Chatam Islands^) is to 

 be referred to the same form. It is nearly hemispherical, about 

 6 cm. in diameter by a thickness of about 3 cm. in the thickest 

 part. The lamels are smaller than in Mediterranean specimens but 

 of about the same thickness, partly rather depressed and irregularly 

 formed over each other partly with more or less cup-shaped or 

 cupulate, now nearly free now hear and there anastomosing lamels. 

 This specimen fuUy coincides in structure with Mediterranean ones, 

 and also as regards the conceptacles of sporangia, except that the 

 latter occasionally are slightly smaller. 



With reference to f. agariciformis formerly considered as a 

 separate species, there has been a good deal of dissent, or diffe- 

 rently interpreted by different writers. The plant described by 

 Areschoug 1. c. under this name belongs to Lithophyllum de- 

 cussatum. Cp. below. Hauch, Meeresalg. considers it a form 

 of Litliophyllum expansum. It has also been considered identic 

 with the plant mentioned below by the name of Lithophyllum 

 dentatum f MacallanaP) On the other hand it is impossible to 

 know what underlies the description by Pa 11 as. But the identily 



1) Cp. Reinbold, Ergebnisse einer Reise nach dem Pacific (Pro f. Dr. Schauins- 

 land 1896—97). Meeresalgen. — Abh. Nat. Ver. Bremen 1899. Bd. XVI. 

 Pag. 300. 



2) Cp. Johnson, A List of Irish Corallinaceæ. — Scientific Proceedings ol 

 the Royal Dublin Society. Vol. IX. (N. S.). Part I. No. 3. Dublin 1899. 



