522 DICKIE ON ARCTIC ALGtM. 



collection, in a recent volume of the Linnean Society's Proceed- 

 ings. 



Of the species enumerated above, the following are truly Arctic : 

 Sphacelaria arctica. Polysiphonia arctica. 



Kallymenia Penny i. Phyllophora interrupta. 



Halosaccion dumontioides. 



General conclusions as to species peculiar to east or west side 

 of the Strait cannot yet be arrived at ; but Callithamnion Ame- 

 ricanum and Kallymenia Pennyi, are as yet known only on the 

 west side. 



Judged by the number of species enumerated in the '* Flora 

 Antarctica," the Arctic Seas, may be said to be rich in AlgcB. 



Three products, usually plentiful in certain marine Algce of low 

 latitudes, are also abundant in some of the Arctic species, namely, 

 the iodides, mannite, and carbonate of lime. Melobesia and 

 Corallina officinalis, of course contain the last. Laminaria sac 

 charina, as its name implies, yields mannite, which appears as a 

 white efflorescence when the plant is dried, without having been 

 washed ; and L. longicruris contains a still larger quantity. The 

 presence of iodides I have also tested in Arctic specimens. A 

 filtered and concentrated solution from a few grains of ash, with 

 nitric acid and starch, is generally sufficient to give, in a rough 

 way, proof of the amount of iodides, as indicated by tints varying 

 from dark-blue, through purple, to pale i*ose ; and where iodides 

 are in small proportion, the last colour may not appear until after 

 a few minutes' 



Fucus nodosus - - - Pale purple. 



F. vesiculosus . - - Pale purple. 



Dictyosiphon foeniculacens - Very dark blue. 



Laminaria longicruris - - Pale rose. 



Ptilota serrata . - . Pale purple. 



Ahnfeldtia plicata - - Pale rose. 



Polysiphonia arctica - - Pale rose. 



Ulva latifolia - - - Pale rose, slowly. 



Conferva melagonium - - Pale purple. 



LXXVII. — Lichens from Barrow and Davis Straits, 

 collected by Dr. P. Sutherland, during Capt. Penny's 

 Arctic Voyage in the " Lady Franklin." By the 

 Rev. Churchill Babington, M.A., &;c. 



From " Hooker's Journal of Botany," vol. iv., pp. 276-8. 1852. 



Lichenes. 



Cladonia rangiferina, Hoffm. Near Cape York. 

 C. pyxidata. Fries. Near Cape York. 

 Everina ochroleuca. Fries. Near Cape York. 

 E. divergens. Fries. Near Cape York. 

 Dufourea ramulosa. Hook. (?) 



