1925] Setchell-Gardner: Melanophyceae 635 



Riipreeht, Neue Pflanzen, 1852, p. 17 (73), pi. 5; Setchell and 

 Gardner, Alg. N.W. Amer., 1903, p. 271 ; MacMillan, Observations on 

 Pterygophora, 1902rt, p. 723, pis. 57-62; Muenscher, Key to the 

 Phaeophyceae, 1917, p. 280, fig. 45; Frye, The Age of Pterygophora 

 calif arnica, 1918, pp. 65-71, pi. 17 ; Farlow, Anderson and Eaton, Alg. 

 Exsicc. Amer.-Bor., no. 114 ; Collins, Holden and Setchell, Phyc. Bor.- 

 Amer. (Exsicc.), no. CVIII ; Tilden, Amer. Alg. (Exsicc), no. 520. 



Pterygophora calif o^'nica is a perennial. No accurate data, 

 obtained from experimental evidence, has yet appeared to indicate 

 the age of this sturdy species of algae. Frye (loc. cit.) has sum- 

 marized the opinions of various writers on the subject and has given 

 the results of his own observations on plants in the vicinity of Blakeley 

 Island and at Cape Flattery, Washington. His results are based upon 

 the number of scars on the stipe, produced by the disintegration of 

 sporophylls, and upon the number of rings in the stipe. Thirteen 

 years is the oldest estimated age of any plant which he has discovered. 



56. Alaria Grev. 



Holdfast comparatively small, of more or less slender branched 

 hapteres from near the base of the stipe, forming a turbinate compact 

 mass; stipe comparatively small and usually short, solid, unbranched, 

 with or w^ithout mucilage ducts; blade terminal, considerably elon- 

 gated, entire, thin, Avith a pronounced longitudinal, percurrent, cen- 

 trally located midrib, usually showing tufts of hairs (cryptostomata) ; 

 sporophylls from both sides of the stipe, of limited growth, developing 

 in the transition region ; sori usually covering nearly the whole of 

 both surfaces of the sporophylls ; perennial. 



Greville, Alg. Brit. Syn., 1830, p. xxxix and p. 25. 



Greville remarks {loc. cit.) concerning the establishment of the 

 genus as follows : ' ' The individuals which constitute this genus I have 

 removed from an assemblage published by Bory de St. Vincent under 

 the name of Agarum.'' The individuals to which Greville refers, as 

 enumerated in the Synopsis, were Agarum esciilentum, A. Delisei and 

 A. Pylaii. As the type of his new genus he selected the first which is 

 the FiicAis esculentus of Turner (1809, pi. 117), this being the only 

 species of the three mentioned by Bory which occurs within the British 

 waters, the other inhabiting "Terre-Neuve." The Vienna Congress 

 has conserved the generic name Alaria Grev. (1830) as against Musae- 

 /o/m Stackhouse (1809) and Orgyia ^tackhouse (1816). 



