680 ZOOPHYTES. 



longitudinally sulcate ; geniculations a little tumid ; polyps with the 

 tentacles ramulous, white. 



Red Sea. Ehrenberg. 



This description is from Ehrenberg. He mentions that the species 

 is an elegant one when alive, though but two inches in height. 



Mopsea erythrcea, Ehrenberg, G. Ixxviii., Isis erythracea, Lamarck, 2d ed., ii. 477, 

 sp. 3. No. 7. 



APPENDIX. The Isis coralloides of Lamarck may belong to this 

 genus. It is thus described by this author (sp. 5): "I. ramosa, dis- 

 ticho-ramulosa, rubens ; ramulis remotis, breviusculis, cortice papillis, 

 raris, ascendentibus." From the " Austral seas." Peron $ Lesueur. 



GENUS II. ISIS. LINN/EUS. 



Isince articulis cornels et cakareis alternis instructs, e nodis calcareis 

 ramulosce ; cortice crasso, deciduo. 



Isinse, consisting of corneous and calcareous joints alternately ; branches 

 proceeding from the calcareous joints ; cortex thick, deciduous. 



The crust of these species is so deciduous that it is rarely seen in 

 collections, although the corals are not uncommon. 



This genus, as instituted by Linnaeus, contained the genus Coral- 

 Liu m as well as Mopsea. 



Isis HIPPURIS. (Linnaus.) 

 I. parce ramosa, ramis crassis, axe calcareo albo, valde sukato. 



Sparingly ramose, branches stout; calcareous joints of the axis white, 

 strongly sulcate. 



East Indies. 



