216 Puget Sound Marine Sta. Pub. Vol. 1, No. 19 



utricles unmodified or characteristically thickened and striated; trichomes 

 wanting; plugs pre'sent only in base of gametangia and at origin of utricle 

 branches; gametes (.'') round, bright green, many; gametangia slender, 

 ovate, 300/x long, 40-50/i, in diameter. 



CONCLUSIONS 



1. The C. adhaerens (Cabr.) Agardh reported from San Juan Is- 

 land, and probably that from all of Puget Sound, is C. dimorphum Sved. 

 in view of the fact that it has no utricle hairs and possesses two types of 

 utricles, the one with unmodified end wall, the other with thickened 

 striated end wall. 



2. The thick-walled type may predominate all over the thallus, or it 

 may be found only around the margin and on the under side of the lobes, 

 or it may be wanting entirel}\ 



3. This variation in the thickness of the end wall of the utricles is 

 probably due to differences in environment. That this dimorphism of 

 the utricles is probably not a physiological dimorphum is indicated by the 

 fact that gametangia have been found quite commonly on the thick-walled 

 type and on their branches. 



CITATIONS 



1. Agardh, C. A. Spec. Alg. p. 457. 1820. 



2. Agardh, J. G. Till Algernes Systematik. VIII. Lunds Universitets 

 Ars-skrift. 23: 37. 1886-1887. 



3. Berthold, G. Uber die Verteilung der Algen im Golfe von Neapel. 

 3: 393-536. 1882. 



4. Collins, F. S. The Green Algae of North America. Tufts College 

 Studies. 2: 386-389. 1905-1909. 



5. Ernst, A. Siphoneen-Studien 2. Beih. Bot. Centralb. 16: 199-233. 1904. 



6. Falkenberg, P. Die Meeresalgen des Golfes von Neapel. Mitteilungen 

 a. d. zool. Station zu Neapel. 1: 217-277. 1879. 



7. Hauck, F. Die Meeresalgen Deutschlands und Osterreichs. Raben- 

 horst's Kryptogamenflora. 2: 477-479. 1885. 



8. Hurd, A. M. Codium mucronatum. Puget Sound Marine Station Pub. 

 1: 109-135. 1916. 



9. Kiister, E. Zur Anatomic und Biologie d. Adriatischen Codiaceen. 

 . Flora. 85: 170-188. 1898. 



10. Muenscher, W. L. C. A Study of the Algal Associatiojjs of San Juan 

 Island. Puget Sound Marine Station Pub. 1: 59-84. 1915. 



11. Oltmanns, F. Morphologie und Biologie der Algen. 1: 297-301. 1904. 



