62 Mr Shuttleworth on the Colouring Matter 



where it was melted, without having previously co-existed 

 with the other organised bodies of the red snow. 



Although the celebrated Algologue Agardh has stated that 

 the Lepraria kennesina of Wrangel is the same production 

 with his Protococcus nivalis, yet this identity I consider to be 

 still doubtful. It is possible ; but I confess I am inclined to 

 believe, that we shall succeed in demonstrating that the pro- 

 duction found hitherto only upon stones, and the decomposed 

 remains of other plants, is a quite distinct organism. After 

 what I have already said, I need not dwell upon the animality 

 of the globules observed by Wrangel, and upon the supposed 

 transition of vegetable globules into infusoria, and vice versa. 



The Scottish plant figured by Dr Greville (which had pre- 

 viously been noted by Agardh as belonging to a distinct genus), 

 and probably even the plant discovered upon the stones and 

 mosses of the polar regions, and described by Hooker, under 

 the name of Palmella nivalis, appear to me not only distinct 

 species, but, if the existence of the gelatinous substratum ob- 

 served by Hooker in the polar plant, and so distinctly figured 

 by Greville, both in it and the other, be verified, then these 

 plants (notwithstanding Mr Harvey's remarks), cannot be con- 

 founded with the Protococcus nivalis, any more than they can 

 even enter mto the genus Hcematococcus, The plant observed 

 upon the stones, «Sjc. near Prague, and figured by Corda, had 

 been before noted by Kutzing (in the Linnea 1833, p. 372), 

 as his Microcyrtis sanguinea {Hcematococcus sanguineus, Ag. 

 Ic. Alg. Eur. No. et Feb. 24.), and apparently correctly. 



Upon the whole, then, it appears necessary to distinguish 

 the different Algae which have been confounded under the 

 name of Protococcus nivalis ; and as, according to my obser- 

 vations, the diagnoses of the genera appear to me no longer 

 satisfactory, I shall now endeavour to propose others, begin- 

 ning with the most simple organization. 



Protococcus, Agardh, Syst. Alg. p. xvii. Globuli liberi 

 sporulis repleti. Protococcus nivalis, Ag. 1. c. p. 13. Icon. 

 Alg. Eur. No. et tab. 21. Pr. nivalis, tabula nostra, f. 2. 

 Uredo nivalis, Bauer, 1. c. Nees ab Esenb. in Brown's Verm. 

 Schrift. i. p. 578, cum icone excl. f. 9. 



The character of this genus will exclude, so far as we ac- 

 tually know, a great portion of the other species w^hLch are 



