BOTANY 



chiefly in the neighbourhood of Penzance, the work has been done by 

 one of the keenest and most careful botanists of the last century, viz. 

 Dr. Ralfs, whose Monograph of the British Desmidiea, published in 1848, 

 is, for lucidity of description and exquisite delineation of the forms of the 

 species, unsurpassed even at the present day. The list of Cornish fresh- 

 water alga? is therefore, especially as far as concerns the DesiauJiaceat, 

 Diafomacece (now usually called the Bacillariacece) and Palmellaceee, un- 

 usually rich as regards records. During the last quarter of the century 

 the materials collected by Dr. Ralfs were carefully collated and added to 

 by Mr. E. D. Marquand, who published an account of the freshwater 

 alga? of the Land's End district in the Transactions of the Penzance 

 Natural History and Antiquarian Society, ii. 133, 380. Other botanists 

 who contributed to this record were Mr. J. B. Major ; Prof. O. Nord- 

 stedt of Lund University in Sweden, who paid a visit to Penzance and 

 detected a number of new species there ; Mr. A. W. Bennett, who 

 searched the north of Cornwall, and Mr. R. V. Tellam, who collected 

 some species in the neighbourhood of Bodmin. In the Land's End 

 district Mr. E. D. Marquand indicates Chy-an-hal and Tremethick 

 Moors as particularly rich in unicellular species, and the dripping rocks 

 between Mousehole and Lamorna, and the coast between Lelant and 

 Carbis Bay as yielding many species not observed elsewhere. The large 

 number of species detected in this small portion of the county suggests 

 that Cornwall is probably one of the richest counties in England in this 

 group of plants, although it is possible that the mountainous counties 

 near the sea, in Wales and the west of Scotland, might be richer in 

 Alpine forms. 



That the list will probably be greatly extended in the future is 

 shown by the fact that many species new to the county, and a few new 

 also to science, are recorded in the "Journal of Botany for February and 

 March, 1903. 



The following are the species new to science : 



Phaeosphaera gelatinosa, West & G. S. West 

 Bumilleria pumila, n. sp. Ic. pi. 446, figs. 



22,23 

 Conferva obsoleta, n. sp. Ic. pi. 446, figs. 



18, 21 



Cosmarium quadrimammillatum, n. sp. Ic. 



pi. 446, fig. 12 

 Debarya desmidioides, West & G. S. West, 



Ic. pi. 446, figs. 1-9 



The species new to the county are : 



Bulbochaete subintermedia, Elfn. Sennen 

 Closterium pusillum, Hantsch. 



var. monolithum, With. Gurnard's 

 Head 



macilentum, Brdb. Mullion 



pronum, Br6b. 

 Euastrum lobulatum, Brb. Tremethick 



Moor, St. Just, Sennen, Land's End 

 Genicularia spirotasnia, De Bary. Hayle 

 Cosmarium Lundelii, Delp. Mousehole 



abbreviatum, Racib. Crowan 



commissurale, Brb. St. Just 



Staurastram granulosum, Ralfs. Crowan 



brachycerum, Breb. Sennen 



vestitum, Ralfs. St. Just 

 Zygnema Vaucherii, C. Ag., var. stagnale, 



Kirchn. Lizard 

 Conferva affinis, Ktltz. South of Helston, 



St. Mary's, Scil/y 



Characiopsis minuta, Borzi. Penzance 

 Centrosphsera Fasciolae, Borzi. Sennen 

 Bulbochaete subintermedia, Ktltz. 

 Euastropsis Richteri, Lagerh. }> 



