THEONOA. 179 



absurd to return to Tilesia, especially as the type species of Theonoa 

 is far more characteristic of the genus than that on which Tilesia 

 was based. 



Theonoa is allied to Actinopora and Kololophos, from which it 

 differs in having the zoarium either massive or in erect, thick 

 fronds, instead of in thin, unilaminar sheets. 



1. Theonoa clathrata, 1 Lamouroux, 1821. 



SYNONYMY : 



Theonoa clathrata, Lamouroux, 1821, Expos. Meth. p. 82, pi. Ixxx. figs. 17, 18. 

 ,, ,, Bronn, 1825, Pflanzenth. p. 21, pi. vi. fig. 20. 



,, Defrance, 1828, Diet. Sci. nat. t. liii. p. 470. 



,, ,, Blainville, 1830, ibid. t. Ix. p. 373, pi. xlv. fig. 2. 



,, ,, Blainville, 1834, Man. Act. p. 408, pi. Ixvii. fig. 2. 



,, ,, M. Edwards, 1836, in Lamarck, Hist. Nat. Anim. s. Vert. 



ed. 2, t. ii. p. 318. 



,, ,, Bronn, 1837, Leth. Geogn. ed. 2, Bd. i. p. 250, pi. xvi. fig. 14. 



,, ,, Morris, 1843, Cat. Brit. Foss. p. 45. 



,, ,, Michelin, 1846, Icon. Zooph. p. 233, pi. Iv. fig. 6. 



,, ,, Bronn, 1848, Nomencl. p. 1268. 



,, ,, Bronn, 1849, Enum. p. 145. 



,, Bronn and Romer, 1851, Leth. Geogn. ed. 3, Bd. ii. Th. 4, 



p. 92, pi. xvi. fig. 14. 

 ,, ,, Haime, 1854, Bry. jurass. : Mem. Soc. geol. France, ser. 2, 



t. v. p. 204, pi. x. fig. 1. 



,, ,, Morris, 1854, op. cit. ed. 2, p. 129. 



,, ,, Terquem, 1855, Pal. dep. Moselle (sep. copy), p. 26. 



,, Pictet, 1857, Traite Pal. ed. 2, t. iv. p. 130. 



,, ,, Ferry, 1862, Bajoc. Ma9on, pt. i. : Mem. Soc. linn. Norm. 



t. xii. p. 14. 

 ,, ,, E. E. Deslongchamps, 1865, Jur. inf. Norm.: Mem. Soc. 



linn. Norm. t. xiv. p. 151. 

 ,, ,, "Waagen, 1868, Zone Amm. sowerbyi: Geogn. Pal. Beitr. 



Bd. i. Ht. 3, p. 643. 



,, ,, Terquem, 1868, in Jacquot, Descr. geol. dep. Moselle, p. 290. 



,, ,, Vine, 1883, 3rd Eep. Foss. Polyz. : Rep. Brit. Assoc. 1882, 



p. 265. 

 ,, ,, Vine, 1888, Polyz. Caen: Journ. Northptn. Nat. Hist. Soe. 



vol. v. p. 20. 



1 Lamouroux spelt the name chlatrata, and this spelling has been adopted by 

 many later authors. As this, however, is meaningless, and is clearly a misprint 

 for clathrata (or lattice -like), the correction proposed by Michelin is here accepted. 



