146 
ORDER II. HYDROIDEA. 
Family IL— SERTULARID^E. | 
Buds persistent ; pol3^ps sessile ; ovules included in a vesicle, j 
lateral. 
The following are the characteristics of the genera. 
I. Polyps in one series, branches therefore secund. > j 
1. Antennularia (Lamarck). J^ot plumose. Calicles tubular or campan- vj 
idate. I 
2. Plumularia (Lamarck). Plumose, pinnate, or decompound pinnate. ^ i 
II. Polyps in two series. 
a. Series uninterrupted. 
3. Sertularia. Calicles urceolate ; attached at base, with the summits m.ore 
or less free. This genus includes the Dynamene, of Lamouroux, which was 1 
instituted for species having the cells opposite, instead of alternate. M 
4. Thuiaria (Fleming). Calicles attached by one side as well as at base, not I 
free at apex. This genus is the Biseriaria, of Blainville, a name substituted f 
by that author for Fleming’s. I 
5. Thoa (Lamouroux). Calicles very short tubular or companulate. The ^ 
habit of the Those, as suggested by Milne Edwards, is much like that of the | 
Campanularise, and it may belong to the following family. I 
b. Polyps in successive groups, arising from a periodicity in budding. f 
6. Pasythea (Lamouroux). 4 
Antennula^ia cyathifera {Dana). — A simple, erect, filiform stem, half 
an inch high ; polyps subremote ; calicles elegantly broad campanulate, with | 
the margin entire; two rudimentary calicles intermediate. | 
Plate 61, fig. 5, zoophyte, unexpanded, enlarged; 5a, same, natural size. | 
Also, figure 9, page 25. — Balabac Passage, East Indies. — Exp. Exp. I’ 
Sertularia mimosa {Dana). — Neat plumiform, 34 inches high, pinnules 
about 4 lines distant, and 9 lines long, calicles short, and sparingly prominent >’ 
polyps very long, exsert, and slender, with the circlet of tentacles placed ob- i 
liquely, elliptical ; tentacles capillary, recurved at apex. 
Plate 61, fig. 6, zoophyte, natural size, partly in outline; 6a, one of the | 
polyps, expanded, and another contracted, natural size.-— The Feejee Islands. | 
—Exp. Exp. ^ . I 
Pasythea gracilis {Dana). — Polyps in successive clusters of six ; calicles f 
opening outward, not inflated at base. i 
Fig. 11, page 25, zoophyte, enlarged. — Gulf-weed, Atlantic Ocean. — Exp. J 
Exp. I 
