HYDROIDS OF BEAUFORT, NORTH CAROLINA. 



347 



Syncoryne miiabilis (Agassiz). 



Corytu mirabilis Agassiz, Cont. Nat. Hist. U. S., IV, 1862, p. 185. 



Syncoryne mirabitis Nutting, Hydroids of the Woods Hole Region, 1901, p. 32S. Hargitt, Am. Nat., 1901, p. 306. 



Trophosome. — Colony unbranched or slightly and irregularly branched; hydranth body large, very 

 stout for its length; perisarc smooth, reaching to the base of the hydranth. 



Gonosome. — Gonophores borne below the proximal tentacles; medusae become sexually mature 

 before being liberated. 



Color. — Hydranth rose red. 



Distribution. — On floating sargassum from the seaward side of Bogue Bank. 



Family BOUGAINVILLID^. 



Trophosome. — Colony usually branching; hydranths that may 

 change from conical to a low dome shape; tentacles filiform but rather 

 short and rigid, arranged in one whorl around the base of the hydranth 

 body. 



Gonosome. — Gonophores producing free medusae borne on the 

 hydrocaulus below the hydranth body; the marginal tentacles may 

 be in clusters. 



Genus BODGAINVILLU. 



Trophosome. — Perisarc well developed on tlie branches as well as 

 on the main stem. 



Gonosome. — Gonophores supported on short pedicels, medusae 

 with four radial canals and four clusters of tentacles. 



Bougainvillia rugosa Clarke. 



Bouffainvillia ruffosa Clarke, New Hydroids from Chesapeake Bay, 1S81, p. 140. 

 Mayer. Ttic Hydromeduss, vol. I, 1910, p. 171. 



Trophosome. — Stem growing from a stolon, fascicled at the base, 

 reaching a height of about 3 inches; branching irregular. None of the 

 branches are so large as the main stem. Commonly these branches 

 remain unbranched, but each gives rise to three or four pedicels for the 

 hjdranths. The peri.sarc extends well up on the hydranth Ix)dy, and 

 the portion thus extended is much corrugated with ridges that pass 

 around the hydranth parallel to one anotlicr. The proboscis is ordi- 

 narily conical, but may be much flattened. The tentacles are few in 

 number, 8 to 10, and short. 



Gonosome. — Gonophores produced from the hydrocaulus below the hydranth body, covered with 

 perisarc. In the free medusa there are four oral tentacles and four groups of three marginal tentacles. 



Color. — Light brown. 



Distribution. — Dredged in Bogue Sound at a depth of 10 or 12 feet; on piles of the wharf at Marshall- 

 berg, near low-water mark. 



Family EUDENDRID^. 



Trophosome. — Colony branching; perisarc well developed; proboscis trumpet-shaped, but with 

 much freedom of movement; tentacles all filiform, in a single whorl. 



Gonosome. — Male and female gonophores bear little resemblance to each other. Male gonophores 

 are usually in whorls, female gonophores usually in clusters. Free meduss are not produced. 



Fig. 4. — Bougainvillia rugosa Clarke. 



A, a fascicled portion of the stem; 



B, a portion of a branch. 



