52 Erstes Kapitel. Historische Einleitung. 



***Sponge massive, with a tubulär cloaca. 



IV. Leucosolenia, Bowerbank. Sponge tubulär, formed of a Single layer 

 of triradiate and other spicula. IV A. Arborescent ( 1 . L. botryoides ). IV B. Massive 

 (Nardoa, 2. L. conlorta, 3. L. lacunosa). IV C. Incrusting. Spicula minute (4. L. 

 coriacea). 



V. L e u c n i a, Grant. Sponge massive, permeated by sinuous canals, strengthened 

 with irregularly placed triradiate and other spicula (1. L. nicea, 2. L. fhtulosn, 

 3. L. punüln). 



VI. Leu cogypsia, Bowerbank. Sponge massive, with oscules on outer sur- 

 face and no cloaca, formed of irregularly disposed membranes and spicula (1. L. Gossei, 

 2. L. algoensis). 



Vn, Clathrina, Gray. Sponge branched; branches slightly corapressed, 

 variously and irregularly anastomosing. Oscules at the end of the smaller branches. 

 Spicula triradiate, rays blunt (C sut füren). 



VIII. Lelapia, Gray. Sponge? Spicules calcareous, elongate fusiforrae, with 

 two more or less elongated nearly parallel branches at oue eud (L. australis). 



Farn. 2. Alcyonccllidae. 



Sponge tubulär, simple or branched. Outer surface tessellated , formed of Square 

 perforated cells. Oscules terminal. 



IX. A 1 cy n c e 11 u m , Blainville. Sponge soft, subgelatinous, slightly branched 

 (A. gelatinosum). 



X. Dunstervillia, Bowerbank. Sponge tubulär, fusiforra or globose, hispid. 

 Surface even, tessellated. Oscules Single, terminal, suiTOunded with two series of 

 cilia , one vertical , and the other expanded horizontally. Spicules of skeleton three- 

 rayed, rays equal; of fringe rigid, fusiform (1. D. tessellata, 2. D. corcyrensis). 



Farn. 3. Aphrocerasidae. 



Sponge tubulär, branched, formed of two coats; outer coat of simple fusiform 

 spicula, placed side by side in the longitudinal axis of the stem and branches. Inner 

 coat and network of interlaced fibres, placed in all directions. Branches simple, 

 attenuated and open at the tip. 



XI. Aphroceras, Gray (A. alcicornis). 



Da dieser systematische Versuch von Gray (wenn wir von O. Schmidt's Ein- 

 theiluug der Kalkschwämme in Solitariae und Sociales absehen) bis auf meinen Pro- 

 dromus der einzige Versuch war, die Genera der Calcispongien in Familien zu ver- 

 theilen, so muss ich hier noch einige kritische Worte hinzufügen. Für Jeden, der 

 nur einigermassen mit der Systematik der Spougien vertraut ist, bedarf es keines be- 

 sonderen Hinweises darauf, dass dies Spongien-System in Bezug auf Willkühr der An- 

 ordnung, völligen Mangel an Logik und Unnatürlichkcit der Auffassung das Aeusserste 



