58 A CATALOGUE OF THE BRITISH MARINE ALG^E 



Gen. 153. ACROCH^ETIUM Nag. (= CHANTRANSIA Sclim., non Fries). 



OBS. As originally constituted by De Candolle, Chantransia 

 was a mere assemblage of individuals without similarity of struc- 

 ture or reproductive function, including species of Lemanea, Ba- 

 trachospernutm, Cladophora, and (Edoyoniiun. As reconstituted by 

 Fries in 1825 (Syst. Orb. Veg. p. 338), with Conferva chalybea and 

 C. Hermani for types, it does not differ in any essential particular 

 from Audouinella, founded by Bory (Diet. Class. d'Hist. Nat. vol. iii. 

 (1823), p. 340) two years earlier. Once more reformed by Schmitz 

 (in Flora, 1889, p. 438), it is synonymous with Acrochatium Nageli, 

 Morph. und Syst. Ceram. p. 402 (1861 ). Under these circumstances it 

 seems to me that either the name Audouinella must be substituted 

 for Chantransia as that genus was understood by Thuret (i. e. to 

 include both fresh-water forms, like C. chalybea and C. Hermani, 

 and marine, like C. corymbifera, C. efflorescens, and C. microscopica), 

 or, as seems preferable, to preserve the former name as that of a 

 doubtful genus of fresh-water algae, and to adopt Nageli's genus 

 Acrochcetium for the reception of the well-understood marine forms. 



oc. 



Parasitic species. 



A. entophyticum Batt. ( = Chantransia entophytica Batt.). Coast 

 of Devon (Plymouth). Very rare. Parasitic in the thallus of 

 Heterosiphonia plumosa. 



A. ChylocladicB Batt. ( = Colaconema Chylocladia Batt.). Coast 

 of Devon (Plymouth, Torquay). Very rare. Parasitic in the thallus 

 of Chylocladia ovalis. f. pulchra Batt. Coast of Bute (Isle of Cum- 

 brae). Parasitic in Sertulari. 



A. endozoicum^aii. ( = Chantransia endozoicaD&rbyslme). Coast 

 of Northumberland (Alnmouth) and S.W. coast of Ireland (Valentia, 

 Co. Kerry). Parasitic in species of Alcyonidium. Very rare. 



ft. Epiphytic species. 



A. trifilum Batt. (= Chantransia triftla Buff ham). Coasts of 

 Devon (Plymouth) and Dorset (Swanage). Very rare. 



A. microscopicum Nag. Coasts of Cornwall (Kynance Cove); 

 Devon (Torquay) ; Northumberland (Berwick). Very rare. 



A. spar sum Batt. ( Callithamnion sparsum Carm.). Coasts of 

 Cornwall (Mount's Bay) ; Sussex (Brighton) ; Durham (Roker). 

 Scotland: Haddington (Dunbar) ; Fife (Earlsferry) ; Kincardine 

 (Bay of Nigg) ; Orkney Islands (Kirkwall) ; Argyle (Appin). Ire- 

 land : Miltown Malbay, Co. Clare. Eare. 



A. mirabile Nag. (= Callithamnion mirabile Kiitz.). Coast of 

 Dorset (Swanage). Eare. 



A. ccBspitosum Nag. (= Callithamnion ccespitosum J. Ag.). Coast 

 of Dorset (Swanage). 



A. virgatulum3.A.g.(= Callithamnion virgatulum . Harv.). Coasts 

 of Cornwall (Trevone Bay, St. Minver, Falmouth, Looe, Tor Point) ; 

 Devon (Plymouth, Torquay, Ladran Bay, Sidmouth) ; Dorset (Wey- 

 mouth, Swanage); Sussex (Brighton); Kent (Dover); Yorks. (Filey, 

 Scarborough); Durham (Sunderlaud); Northumberland (Alnmouth, 

 Berwick) ; Isle of Man; Cheshire (Hilbre Island, Easthani). Wales: 



