[310]

Proc. Zool. Soc. 1897, p. 818.

[311]

Zeitschr. f. wiss. Zool. lxiii. 1898, p. 489.

[312]

Quart. Journ. Micr. Sci. xlvi. 1902, p. 1.

[313]

Zool. Zentralbl. x. 1903, p. 27.

[314]

For a discussion of the origin of the polysiphonic stem in Calyptoblastea see Nutting, "American Hydroids," Smithsonian Institution Special Bulletin, pt. i. 1900, p. 4.