19--5] SetcheJI-fjarchier: Mclanophijceae 659 



base on the substratum, serving as attaching organs ; cells dividing 

 horizontally 1-3 cells back of the margin, making the main body of 

 the frond distromatic ; marginal layer of 1-3 cells monostromatic ; cells, 

 in surface view, quadrangular, 16-24ju, long, 10-12ju broad, marginal 

 cells 30-50ja long, containing numerous, small, spherical chromato- 

 phores ; sporangia pyriform to ellipsoidal, 32-3Sjji, long, 28-32/^ broad ; 

 aplanospores (?) 4-5ju, diani., numerous; paraphyses clavate, 4-7 cells 

 long. 



Growing attached to shells of mollusks in 10-15 fathoms. Griffin 

 Bay, San Juan Island, Washington. 



Setchell and Gardner, Phyc. Cont., A^T, 1924, p. 11. 



63. Zonaria Ag. (lim. mut.) 



Fronds in part decumbent or wholly erect, decidedly stupose at 

 the base, ecostate at first, the margins soon wearing away in the lower 

 part, thus becoming stipitate and subcostate by thickening, flabellately 

 divided ; growth in length by means of numerous cells at the ter- 

 minal edge; fronds composed of two tissues, a medullary layer of 

 several cells, and a single cortical layer, arranged more or less in longi- 

 tudinal rows, containing many chromatophores ; antheridia and aplano- 

 spores unknoAvn ; oogonia on one or both sides of the thallus, borne in 

 small sori, among paraphyses. 



C. A. Agardh, Syn. Alg. Scand., 1817, p. xx (lim. mut.) ; J. G. 

 Agardh, in Linnaea, vol. 15, 1841, p. 444, Bidrag till Alg. Syst., I, 

 1873, p. 45 ; Anal. Alg. Cont. I, 1894, p. 12. 



We have taken the genus Zonaria in the broader sense and includ- 

 ing certain of the segregated genera of J. G. Agardh, such as his 

 Gymnosorus, Homoeostrichus, and Stypopodium. This is the sense in 

 which Howe has used it in the Bahama Algae (1920, p. 594). While 

 Homoeostrichus has certain very distinct species, there seems to be 

 less distinct cleavage for certain others. Our single species seems 

 clearly of Zonaria' in this broader sense. 



Nieuwland (1917, pp. 51, 52) has proposed the name ViUa.nia 

 instead of Zonaria (J. G. Agardh, 1872, p. 45) because of a most con- 

 vincingly evident misprint of "Zonaria" for "Zornia." Such an 

 attempted application even of the principle : ' ' once a synonym always 

 a synonym" seems a " reductio ad absurd urn " and especially when 

 applied by one seemingly in absolute ignorance of the genus affected, 

 other than as an abstract entity. Zonaria, however, dates back to 



