214 



PORPIT^. 



Suborder PORPIT^ Goldf. 



Porpitce Goldf. Handb. der Zool. 1820. 



Pnrpitce and Physalice Agass. Cont. Nat. Hist. U. S., IV. p. 366. 



Chondropliorce Cham, et Eys. Acta Nova, X. 



1862. 



From a comparison of the young stages of Nanomia with the known 

 Siphonophoraj, 1 have been induced to extend the hmits of this sub- 

 order so as to include PhysaHa, forming thus three suborders among 

 Hydroids of the old order of Siphonophorse, the Diphya3, the Pliyso- 

 phora?, and the Porpitse. 



Family PHYSALID^ Brandt. 



Physalidm Br. ; in Mem. Acad. St. Petersb., p. 236. 1835. 

 PhysalidcE Agass. Cout. Nat. Hist. U. S., IV. p. 366. 1862. 



PHYSALIA Lamk. 



Phjmlia Lamk. An. s. Vert., HI. p. 89. Second Edition. 



Arethitsa Bro-w^x. Nat. Hist. Jam. 



Are.thma Less. Zooph. Acal., p. 530. 1843. 



Physalia Agass. Cont. Nat. Hist. U. S., IV. pp. 335, 366. 1862. 



Fig. 351. 



Physalia Arethusa Til. 



Physalia Arethusa Til. ; in Krusenst. Reise, PI. 23, Figs, 1-6. 1813. 

 Physalia Arethusa Olf. ; in Mem. Berl. Acad., PI. 1. 1832. 

 Physalia Arethusa Agass. Cont. Nat. Hist. U. S., IV. pp. 335, 367, 



PL 35. 1862. 

 Physalia lielasgica Bosc. Hist. Nat. d. Vers, II. p. 168. 

 Physalia auricjera McCr. Gymn. Charleston Harbor, p. 74. 



Physalia Arethusa (Fig. 351) is probably carried 

 by the Gulf Stream as far as the Azores. A spe- 

 cies has been described by Lesson as Physalia 

 azoricum, which may be only the young of Phy- 

 salia Arethusa. (See Voyage de la Coquille, Plate 

 5, Fig. 4.) To facilitate the comparison of the 

 different kinds of individuals found in communi- 

 ties of this family with those of Nanomia, groups 



Fig. 351. Physalia Arethusa Til. Figs. 351-354 are copied from 

 Professor Agassiz's Contributions, o, blunt end of air-sac supporting 

 the community ; 6, open end of air-sac ; c, crest of air-sac ; m, bunches 

 of single individuals ; «, tentacle contracted ; ^, t, tentacles of the lai*- 

 gest kind expanded. 



