[729] INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. 335 
RHEGMATODES TENUIS A. Agassiz. (p. 454.) 
In Agassiz, Contributions, vol. iv, p. 361, 1862; Catalogue, p. 95, figs. 136-138. 
Buzzard’s Bay and Vineyard Sound. 
ZYGODACTYLA GRENLANDICA Agassiz. Plate XXXVI, fig. 275. (p. 
449.) 
Contributions, vol. iv, p. 360, 1862; A. Agassiz, Catalogue, p. 103, figs. 153-156. 
Aiquorea Grenlandica Péron and Lesueur, Aun. du Mus., vol. xiv, p. 27, 1809 
(t. A. Agassiz). 
Buzzard’s Bay to Greenland. Common in Vineyard Sound, in June 
and July. 
ALQUOREA ALBIDA A. Agassiz. (p. 454.) 
In Agassiz, Contributions, vol. iv, p. 359, 1862; Catalogue, p. 110, figs. 160-162. 
Buzzard’s Bay (A. Agassiz). 
TIMA FORMOSA Agassiz. (p. 449.) 
Contributions, vol. iv, p. 362, 1862; A. Agassiz, Catalogue, p. 113, figs. 164-172. 
Vineyard Sound,. February and April. Massachusetts Bay (A. 
Agassiz). 
EUTIMA LIMPIDA A. Agassiz. (p. 454.) 
In Agassiz, Contributions, vol. iv, p. 363, 1862; Catalogue, p. 116, figs. 173-178. 
Buzzard’s Bay, Naushon (A. Agassiz). 
LAFOBA CALCARATA A. Agassiz. (p. 408.) 
Catalogue, p. 122, figs. 184-194. Lafewa cornuta Agassiz, Contr., vol. iv, p. 351 
(not of Lamouroux). Laodicea calearata A. Agassiz, in Agassiz, Contributions, 
vol. iv, p. 350, 1862. Campanularia dumosa Leidy, op. cit., p. 1388, 1855 (not of 
Fleming). 
South Carolina to Vineyard Sound; Buzzard’s Bay and Vineyard 
Sound. The hydrarium was abundant on floating Zostera and alge in 
Vineyard Sound, creeping over Sertularia cornicina; also at low-water, 
and in 6 to 8 fathoms on Phyllophora ; Thimble Islands, in tide-pool, on 
Vesicularia. Charleston, South Carolina (McCready, described as a 
constituent part of his Dynamena cornicina). 
HALECIUM GRACILE Verrill, sp. nov. (p. 328.) 
Stems slender, flexible, clustered, compound, consisting of many very 
slender, united tubes, light brown or yellowish, pinnately much branched ; 
branches alternate, ascending, long, slender, tapering, similar to the main 
stem, and usually similarly subdivided; the branches and branchlets 
mostly arise from opposite sides of the stem, so that they stand nearly 
in one plane; ends of branches and the branchlets simple, very slender, 
translucent, whitish, divided into rather long segments; the articula- 
tions not very conspicuous, somewhat oblique; each segment usually 
with a prominent cylindrical process, arising from near the upper end, 
which, on the older branches, bears the hydroid cell, but on the young 
branchlets are themselves hydroid cells, furnished with a thin, slightly 
