352 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Gonosome. — Unknown. 
Distribution. — On piles, Greenport, Rhode Island. 
I have a specimen that to a certain extent intergrades between this species and the preceding, 
and therefore suspect that the two species may be identical. 
GONOTHYRXA. 
Trophosome. — Stem not fascicled, branched. Hydrothecse campanulate, with toothed margins. 
Gonosome. — The gonangia producing fixed, medusiform sporosacs with apical filiform tentacles. 
The gonophores, when nearly mature, pass out of the 
gonangium and remain attached to its top until the 
spermatozoa or planuke are discharged. 
Gonothyraea loveni Allman. Fig. 42. 
(Ann. and Mag. of Nat. Hist., 3d series, vol. 13, p. 374.) 
Trophosome. — Stem irregularly branched, attain- 
ing a height of one-half to three-fourths inch, slightly 
tiexuose, annulated above origins of pedicels. Pedi- 
cels short, with 2 to 5 annulations. Hydrothecse 
deeply campanulate, gracefully tapering toward base, 
very thin and transparent around margin, which is 
quite variable in its dentition, the typical teeth being 
turreted and squared at the ends. 
Gonosome. — Gonangia large, long, obconic, borne 
in the axils of the pedicels, each bearing, when ma- 
ture, 3 to 5 modified medusse on its summit. The 
sporosacs are attached to the top of the gonangium 
by short pedicels, and have at their upper end a circlet 
of short tentacles. They discharge their contents 
before becoming free. 
Distribution. — Found on shells, stones, etc., in 
shallow water. Dr. II. C. Rumpus kindly sent to the 
writer some beautiful specimens from the coast of 42 ' Gmiotliy rxa loveni AUm. 43. Gonothyrxa tenuis Clark. ? 
Rhode Island. 
Gonothyrxa tenuis Clark, fig. 43, is reported from New Haven. There is no point either in the 
original description or in the figure published by Dr. Clark that enables me to separate this species 
from typical specimens of G. loveni from England. . Professor Verrill says of this species: “Closely 
allied to G. loveni, but has narrow, elongated, obconic gonothecse.” As these terms are precisely 
applicable to the gonangia of G. loveni, 1 can not perceive any basis for considering G. tenuis a good 
species. 
Gonothyrxa hyalina Hincks is also reported by Professor Verrill as occurring off Watch Hill, 
Rhode Island. The writer, while at Plymouth, England, found completely intergrading specimens 
between this species and G. loveni. 
HEP, ELLA (modified). 
Trophosome. — Pedicels arising from a creeping rootstock. Hydrothecae tubular, with entire 
margins and without opercula. Hydrothecal cavity separated from that of the pedicel by a partial 
septum. Hydranth with a conical proboscis. 
Gonosome . — Gonangia producing free medusae. 
The genus as here defined would include several species whielnnost authors place in the genus 
Lafcca. 
Key to species of Hebella found in the Woods Hole region. 
Hydrothecse usually in pairs, doubly curved. Species almost always parasitic on Sertularia cornicina H. calcarata. 
Ilydrothecae irregularly distributed, small, not doubly curved. Species parasitic on various hydroids II. pygmsea. 
