107 



himself, this species appears to show greatest affinity to L. incru- 

 stans, from which it, however, is distinguished especially with re- 

 gard to the shape and size of the conceptacles of sporangia, as 

 well as the sporangia themselves. 



Habitat. On the Norwegian coast it lives in the upper part 

 of the sublitoral region, on about 5 — 6 fathoms water, both on 

 open coast and in sheltered places. Specimens collected in June 

 to September were provided with conceptacles of sporangia in de- 

 velopment. I, however, did not succeed to find the sporangia. 

 On the coast , of Novaya Zemlya it bears young conceptacles at 

 the end of June and July. Specimens from Spitzbergen probably 

 taken in July or August were furnished with well developed spo- 

 rangia, and on the coast of Greenland in the later half of June. 

 In American specimens collected in July and September I partly 

 found apparently mature sporangia partly in development. Cysto- 

 carpic and antheridian conceptacles still are unknown. 



Occurrence. Found at Kjelmo (Sydvaranger) and Mehavn in 

 East-Finmarken, Kistrand and Kvalsund in West-Finmarken, at 

 Skorpen in Kvamangen, and at Tromso, everywhere apparently rare. 



Geogr. Distribution. Novaya Zemlya (Kj ell man); Spitzber- 

 gen; Greenland (Rosen vinge); the Atlantic coast of North America 

 (Farlow, Collins). 



Lithothamnion testaceum Fosl. mscr. 



L. fronde Crustacea, crustis superimpositis demum usque ad 

 1 cm. crassa, pallida rosea, superficie ineequali, tuberculis subse- 

 miglobosis vel irregularibus instructa; conceptaculis sporangiferis 

 sub foveola leviter excavata immersis, diametro 100—140 /*; spo- 

 rangiis quaternas sporas foventibus, 90 — J20 !->- longis, 25 — 50 ;j- 

 latis. Tab. 19, fig. 5 — y. 



Description of the species. The plant forms irregular crusts 

 of a rose pink colour, older sometimes with a yellowish tinge. 

 The form of the crust partly depends on that of the substratum. 

 New crusts are formed upon the primary, sometimes rather closely 

 clinging to the subjacent sometimes loosely covering extraneous 

 objects, or partly nearly free, with concentric striae in the part 



