ON FOSSIL POLTZOA. 101 



Genus Aetea, Lamouroux. 



1812. Aetea, Lamx , Busk, Smith. 1812. Anguinaria, Lamk (with- 

 out character), Johnston. 1815. Falcaria, (3, Oken. Cercaripora (for 

 Aetea truncata, 8fc), Fischer. 



Generic character. Zocecia calearpous, tubular, erect, with a mem- 

 branous area on one side ; distributed along a more or less adherent, 

 creeping fibre, dilated at intervals ; orifice terminal. Occcia none. 

 Hincks (op. cit. p. 3). 



Mr. A. W. Waters (' Bryozoa Nap.' op. cit. 1879, p. 115) says : ' I have 

 noticed in the Brit. Mns. Collection that the Aeteidce dissolved the shells 

 on which they grew, and thus a permanent record is left. It is known 

 that several Bryozoa have this power ; and the idea suggests itself that 

 some of the phenomena mentioned by Fischer l are of this kind, and it 

 may not be useless to point out that in many cases it is impossible to 

 distinguish fossil Aetea from Hippothoa.' I am glad to give currency to 

 these hints, because in the Palaeozoic rocks of Cincinnati there is a 

 species described by E. 0. Ulrich, which he named Ropalonaria venosa, 

 Ulrich, which the author describes as being related to Hippothoa (which 

 I question) 'but in the form and arrangement of the cells they differ 

 widely ' (' Cin. Soc. Nat. Hist. A.p.' 1879;. I have in my possession a 

 specimen of this species incrusting the Coral Sireptelasma comiculum, 

 Hall, and wherever the cells are broken the former existence of the 

 fossil may be traced by the method of ' dissolving ' referred to by 

 Mr. Waters. Two species of Aetea are recorded by Manzoni : — 



1. Aetea eecta, Hincks=? R. sica, Couch: Manzoni = Hippothoa 



sica, Conch? (See Hincks's note, p. 7, 'Brit. Mar. Pol.') = 

 Stomatopora gallica, D'Orb., 'Pal. Franc. Terr. C ret.' v. 836= 

 A. sica, Norman, 'Quart. Jour. Micr. Soc' n. s. viii. 216= 

 A. anguina, B, forma recta, Smitt (see ref. in Hincks) =-1. sica, 

 Couch, Manzoni, ' Castrocaro,' p. 6, pi. vii. fig. 69. 2 



2. Aetea ANGUINA, Hincks (Busk, Heller, Smith, Norman). A. an- 



guina, Hincks. (Manzoni, ' Castrocaro,' p. 6, pi. vii., pi. vi. 

 fig. 70.) 

 Both these species are described as ' frequent ' by Manzoni at Castro- 

 caro, and also living. 



A long list of synonyms of this species is given by Hincks, ' Brit. 

 Mar. Pol/ p. 4. 



Family II. Euceatiim:, Hincks. 



This family embraces the genera Eucrafea, Lamx. ; Gemellaria, Savigny ; 

 Scruparia, Hincks ; Hu.deija, Dyster, and Bretlia, Dyster, and the whole 

 of the Family Gemellaripje, Busk, except the anomalous genus Notamia 

 (Dimetopia and Calwellia). Didgmia is distinguished by a different 

 type of cell. 



Genus Eitckatea, Lamx., 1812. 



1812. Eucrafea, Lamx., Johnston, Smitt. 1813. Scruparia, Oken, 

 Busk ; Sertularia, (pt.) Linn. ; CeUnlaria, (pt.) Pallas ; Cellaria, (pt.) Ellis 

 and Sol. 1830. Unicellaria, (pt.) Blainv. 1850. Catenaria, (pt.) D'Orb. 



1 Ilypoplwrdla expansa, ' Ein Eeitr. zur Kenntn. der minirenden Bryozoen, 

 von Eblers, Kon. Gesellsch. d. Wissensch. Gottingen, 1867. 



2 Alecto parasita, Heller : Manzoni in Index to Plates, p, 63, 'Castrocaro.' 



