146 ACALEPHS IN GENERAL. Part I. 



Forljes. Those affinities I have recognized in uniting the Ilydroids and Gjni- 

 nophthahnata with the Siphonopliora^ in one order, to which I have Uitely added 

 the TabuUita and Rugosa of Mihie-Edwards. This step seems to me to have at 

 List circumscriljed the class within its natural limits, and iixed its boundaries on 

 the side of the Polyps, where the dividing line had remained more vague than 

 in any other direction. 



I have already 2)resented my objections to some ^joints of the classification of 

 Vogt relating to the Acalephs in general. I have only to give here an outline 

 of the minor divisions which he admits among these animals. But while I cannot 

 agree with his classification, it is but justice to him to say that his paj^er upon the 

 Siphonophora' of Nizza is one of the most valuable contributions of modern times 

 to the natural history of these animals, forming, in connection with similar papers 

 hy Leuckart, Kolliker, Gegenbaur, and Huxley, a very fall description of all the 

 representatives of this type. 



CLASSIFICATION OF VOGT, 18.51. 



RefL'iTing the Ctenopliora3 to the Molhisks, Vogt, in liis " Zuohagiselie Briefe," published in 1851, has 

 adopted the following classification for the Acalephs, after dividing the Radiata into four classes : Polyps, 

 including Lucernaria but not the other Ilydroids, Htjdromedusce, Siplionojyhorts, and Hchinodey-ins. 



The class of IIydromedusaj (Quallenpolypcn) is divided into two orders : — 



1st Order. J/i/dmids, with three families : Ilydrida, Tubularida, Cami>aindari(la. 



2d Order. Mediiscc, with six families : Meilusida, Oci'anida, ^Erpiorida, ISerenicida, Rhizostomida, 

 Gcryonida. 



The class of Sipiiu.voi-iiok.e (Riihrenciualien) is divided into three families: Pliys.alida, Velellida, 

 and Diphyida, to which Stephanomia is appended. 



The class of Ctexophok.e (lvi|)ponquallen) is divided into two families: Beroida and Callianirida. 



In his paper upon the 8iphono]ihora> of Nizza, pulilished in 1854, Vogt has a)ipended the follow- 

 ing classification of the order of his IIydromedusa>, which embraces them: — 



Order I. Poi.Yfi neciialet. 



1st Division. With active natatory organs. Polyps provided with fishing threads. Swimming belly 



hollow. 



Ist Family. Ai/a/mides : A])(ilemia, Agalnia, Pliys()[i]iora. — The genera Rhizojdiysa, Brachysoma, 



Stephanomia, Epibulia, Sarcoconns, and Disculabe, are considered as founded 



upon mutilated animals. 



2d Family. Hippopodides : Ilippopodius, Vogtia. — Elephantopes and Racemis are questionable. 



3d Family. Diphijides : Praya, Galcolaria, Diphyes. All the other genera referred to this 



family are rejected. 

 4th Family. Atlion/hidcs : Athorybia. — The genus Anthophysa is questioned. 

 2d Division. With passive natatory organs. 



1st Family. IVii/salidcs : Pliysalia. — The sub-genera Salacias, Cystisoma, and Alophotes, are 



considered as useless ; and Angela as probably near Physalia. 

 2d Family. J'elel/ides : Velella and Poi'pita. — Rataria is young Velella. 



