A HISTORY OF CORNWALL CYANOPHYCE^: RHODOPHYCE.E Gongrosira viridis, Kiltz. Tremethtck Chantransia Scotica, Kiitz. Mousehole Hapalosiphon Hibernicus, West & G. S. Sacheria mammillosa, Sirod. Penzance West. Sennen In Mr. Marquand's list no definite localities are given, and where records are not obtainable elsewhere, W.C. indicates that his list is the authority for their record in this part of the county. The species re- corded by him as rare are indicated by an asterisk. E.G. and N.C. indicate East and North Cornwall respectively. Scbizotbrix Cresswellii is only found elsewhere at Sidmouth in Devon. Cosmarium commisurale is found nowhere else in the British Islands so abundantly as in Cornwall, and C. quadrimammillatum has not been observed elsewhere in Britain. The genus Centrosphcera is new to Britain, and Euastropsis Richterl has previously only been found in Germany and Norway ; Mougeotia ge/atinosa, elsewhere in Wales and Scotland, in one locality in each ; Genicularia Spirotcenia is the rarest of all desmids ; Gongrosira viridis is known only elsewhere in the British Isles from Lough Beg, Londonderry. CYANOPHYCEJE CHROOCOCCACEJE Chroococcus turgidus, N2g. W.C. Gloeocapsa *coracina, Ktitz. Carbis Bay livida, Carm. Carbis Bay quaternata, Ktitz. Aphanocapsa virescens, Rab. Carbis Bay Aphanothece microscopica, Nag. Microcystis marginata, Kirchn. Coelosphasrium Kutzingianum, Nag. Car- bis Bay Merismopedium glaucum, Nag. Carbis Bay OsCILLATORIACE-ffi Schizothrix *Cresswellii, Harv. Mousehole
- rubra, Menegh. Mousehole
- tinctoria, Gom. Newbridge near
Penzance Microcoleus vaginatus, Gom. W.C. Plectonema Tomasinianum, Born. Symploca muscorum, Gom. Lyngbya ochracea, Thur. Phormidium autumnale, Gom. inundatum, Kiltz. W.C. papyrinum, Bory. Oscillatoria amphibia, C. Ag. W.C. limosa, C. Ag. W.C. nigra, Vauch. princeps, Vauch. splendida, Grev. subfusca, Vauch. inq. W.C. tenuis, C. Ag. W.C. Beggiatoa leptomitiformis, Trevis. (?) W.C. Spirulina *oscillarioides, Turp. inq. RlVULARIACEJE Isactis *plana, Harv. Mousehole Rivularia dura, Ktitz. W.C.
- granulifera, Carm. Carbis Bay
Gloeotrichia Pisum, Thur. W.C. SIROSIPHONACE.S Gongrosira viridis, Ktitz. Tremethick
- Hapalosiphon Hibernicus, West & G. S.
West. Sennen Stigonema minutum, Hass. W.C. ocellatum, Thur. W.C. panniforme, Gom. ScYTONEMACE-ffi Scytonema Hoffmanni, C. Ag. W.C. Myochrous, C. Ag. W.C. Tolypothrix lanata, Wartm. W.C. NOSTOCACE^E Nostoc *caeruleum, Lyngb. Chy-an-hal Moor microscopicum, Carm. W.C. muscorum, C. Ag. verrucosum, Vauch. Anabaena catenula, Born. & Flah. W.C. Flos-aquae, Breb. W.C. oscillarioides, Bory. Chy-an-hal Moor torulosa, Lagerh. variabilis, Ktltz. Hayle Cylindrospermum stagnale, Born. & Flah. W.C. BACILLARIACE-fl: (Diatoms) NAVICULACE-ffi Navicula aestiva, Donk. W.C. amphisbaena, Bory. aspera, Ehr. bacillum, Ehr. biceps, Ehr. borealis, Ktltz. cancellata, Donk. Cluthensis, Greg. crabro, Kiltz. var. pandura, Rabenh. cruciformis, Donk. f)2
