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SUBORDER II.—ALCYONARIA. 
Subfamily III. — ISIN.^. 
Gorgonida 3 forming a jointed axis. 
Genus I. — MOPSEA.— Lamouroux. 
Isinse having the joints alternately calcareous and corneous; 
ramose, with corneous axils; cortex thin. 
1. Mopsea DicHOTOMA (Pallas,) Lamour(^ux. — Five inches high ; ramose, 
dichotomous, branchlets ] line thick ; calcareous joints laterally compressed 
or subcylindrical ; main stem 3 lines thick. 
Indian Ocean. 
2. Mopsea encrinula {Lamarck^) Ehrenherg. Ramose, subbipinnate; 
branchlets filiform, verrucose ; verrucse scattered, ascending, sometimes verti- 
cillate. 
Seas of New Holland. — Peron Lesneur. 
3. Mopsea gracilis [Lamouroux^) Ehrenherg, — Explanate at base, lacin- 
iate; calcareous joints of stem a little stout, those of the branches very long, 
translucent, smooth, white. 
The Antillas. — Lamouroux. 
4. Mopsea erythr^a [H. ^ Ehrenherg). — Dich(Jtomous, frnticulose, ver- 
rucose, scarlet; joints concealed by the cortex; scarcely narrower at the 
geniculations ; branches flexible at the geniculations ; calcareous joints of the 
axis somewhat terete, longitudinally sulcate ; geniculations a little tumid; 
polyps with the tentacles ramulous, white. 
Red Sea. — Ehrenherg. 
^Qppendix. — Isis coralloides {Lamarck). — From the Austral Seas.” — 
Peron ^ Lesueur. 
Genus II. — ISIS. — Linn^us. 
Isin80 consisting of corneous aifid calcareous joints alternately; 
branches proceeding from the calcareous joints; cortex thick, 
deciduous. 
Isis hippuris {Linnaeus). — Sparingly ramose, branches stout; calcareous 
joints of the axis white, strongly sulcate. 
East Indies. 
