HORN i: KID i: M>7 



Family III. Horneridse. 



H..I:SEKID.E, Smitt, Kritisk Fort. 1866. 

 CRISINIIKE (part.), D'Orbigny. 

 LES Tuui'uroRiENs (part.), Milne-Edwards. 

 IDMONEID.E (part.), Busk, Crag Pol., and B.M. Oat. 

 IDMONEAD.E (part.), id. Engl. Cyclopaedia. 



ZOOICIA opening on one side only of a ramose zoarium, never 

 adnate and repent. 



Genus HORNERA, Lamouroux. 



Der. Named after M. Horner, astronomer to the expedition round the 

 world under Krusenstern. 



MILLEPORA (part.), Linn. : Pallas: Solander: &c. 



HORNKRA, Lamx.(1821): Milne-Edwards (part.): D'Orbigny: Smitt: Busk: 



&c. 



BETEPORA (part.), Lamk. : Goldfuse. 

 SiriiODicTvrM, Lonsdale. 



GENERIC CHARACTER. ZOARIUM erect, ramose, some- 

 times reticulate. ZOCECIA tubular, opening on one side only 

 of the branches, disposed in longitudinal series, the czllife- 

 rous surface often traversed by wavy anastomosing ridges. 

 OCBCIUM a distinct chamber (not a mere irregular inflation 

 of the surface of the zoarium), placed dorsally or in front. 



THE genus Hornera is connected with the Tubuliporidte 

 through Idmonea, to which it bears in many points a very 

 close resemblance. It embraces two very characteristic 

 groups : in one the zooccia are covered in front by a cal- 

 careous crust, which takes the form of wavy longitudinal 

 ridges, often anastomosing, which wind round and inclose 

 the orifices of the cells, and give a iihrou.s appearance to 

 the surface of the zoarium. Of this section, which may 



2n 2 



