Htematococcus.] ALGiB GLOIOCLADEiE. 395 



carp, inclosing an uniform coloured mass, and he considers our 

 British plant to be a different species, belonging- to the genus 

 Htematococcus. Having minutely examined a specimen from 

 Agardh himself, submitted to me for that purpose by Dr. Gre- 

 ville, and finding exactly the same compound structure as in 

 our British specimens, I do not hesitate to pronounce the two 

 plants identical. 



1. P. nivalis, Ag. (crimson Protococcus or Red-Snow); "glo- 

 bules exactly spherical very minute fine purple-red, gelatinous 

 mass pale spreading." Gre.v. Crypt. Fl. t. 231. (admirable). — 

 Ag. Syst. Alg. p. 13, et Ic. Alg. Europ. t. 21. — Haimatococcus 

 Grevillii, Ag. Ic. Alg. Europ. t. 23. — Palmella nivalis, Hook, in 

 Parr. 2d. Voy. App. — Vredo ?iivalis, Bauer. 



" On the borders of the lakes of Lismore, spreading over decaying 

 leaves, &c. ; but in greater perfection on the calcareous rocks, within 

 the reach of occasional inundation." Captain Carmickael. Near Miltown 

 Malbay, on schist; at Limerick, on limestone; and about Dublin, on 

 granite; in most cases slightly inundated, W. //. Harvey. — This curious 

 little plant, which, under the name of Red Snow, has excited no in- 

 considerable interest among the greatest botanists of the age, is usually 

 found in this country in the form of a thin, stain-like stratum, on the 

 surface of rocks or investing decayed vegetable substances with a pur- 

 ple crust. It was brought by Captain Ross from the Arctic regions, 

 where it was observed covering the surface of the snow, in patches 

 of many miles in extent, and penetrating in some places to the depth 

 of twelve feet. It has likewise been found to occur commonly, on most 

 of the mountains of Europe, in similar situations. 



93. KLematoc ;6ccus. Ag. Hsematococcus. 



Globules naked, containing granules, aggregated into a frus- 

 tulose CTUSt. — Name; a//xa, blood, and xoxxog, t\w fruit; many of 

 the species are of a red colour. 



1. II. frustulosus, llarv. (grayislMavk Hamotococcus); crust 

 widely spreading friable dark-gray, globules roundish hya- 

 line including numerous scattered minute granules. — Pabnetta 

 frtutuloea, ( '(irm. MSS, 



On irrigated cliffs, perennial, Capt, Carmickael. — "It occurs in the 

 form of a grayish-black, fragmentary scurf. <>n the slightest pressure, 

 it separates into corpusculea of various forms, but mostlj Bphaencal, hya- 

 line under the microscope, surrounded l>> a membranous envelope in- 

 cluding several granules." ('arm. A' 



2, H. tanguineuij Ag, (red Hcematococcus); crust spreading 

 lofi triable of a brick-red colour, -lobules polymorphous in- 

 eluding 1 — ; > granule Ag, Ic, Alg, I'm,, p. t. 24.— Patmeliaf 



tamgtUnea, Ag, Syst, Alg. p. 15. — PaimeUaf cryptopkyUa, Varm. 

 MSS, cum " "i" . 



'•on a stalactitic incrustation, lining tin- vault ol i in a 



quarts rock, Appin," CapL Carmickael. — "This singular production 



, ads over the drj roof of the cavern t.» the extent of several \ Bros, 

 in the torn i of a thick uneven effiore* ence, of a brick-red colour exti r- 



