I13M0NEA SERPENS. 453 



Idmonea serpens, Liimeeus. 



Plate LXI. figs. 2, 3, and Plate LX. fig. 2. 



Small purple Eschara, Ellis, Cor. 74, uo. 6, pi. xxvii., c, B. 



TuBiPORA SERPENS, Liivi. Sjst. Nat. ed. 12, 1271. 



Mii.LEPORA liliacea, Pall. Blench. 248. 



Millepora tubulosa, Ell. df- Sol. Zooph. 136. 



TuBULiPORA TRANSVERSA, LamJc. An. s. V. ed. 2, ii. 242: Lamx. Expos. Meth. 

 1, pi. Ixiv. fig. 1 (after Bills) : Blainv. Actinol. 424 : Eischer, 

 Bryoz. du Sud-ouest de la France (1870), 10. 



Idmonea transversa, M.-Edw. Ann. Sc. Nat. ser. 2, ix. 218, pi. ix. fig. 3 : 

 B'Orh. Pal. Fr. terr. cret. v. 731. 



? Idmonea dilatata, id. loc. cit. 731. 



Obelia tubulifera, Lamx. Exp. Meth. 81, pi. Ixxx. figs. 7, 8 (young state 

 of the present species) : (Reptotubigera) Z*' Orb. loc. cit. 752. 



? Reptotubigera confluens, id. loc. cit. 



TuBi'LiPORA poraminulata, Blaiiiv. Actinol. 425, pi. Ixii. figs. 3, 3 a. 



TuBULiPORA SERPENS, Fkm. B. A. 529 : Couch, Corn. Faun. iii. 105, pi. xix. 

 fig. 6 : Johnst. B. Z. 2ud ed. 275, pi. xlvii. figs. 4-6 : Alder, 

 Northumb. Cat., Trans. Tyues. Nat. F. 0. 1857, 46 (sep.) : 

 Busk, B.M. Cat. iii. 25, pi. xxii. : &c., &c. 



Id.monea serpens. Van Ben. Bull. Ac. Roy. Belg. xvi. no. 12, 647 (5 sep.), 

 pi. i. figs. 7-9 : Sinitt (svibgen.), loc. cit. 399, pi. iii. figs 1-5, 

 and pi. ix. figs. 1, 2. 



Zoarium either wholly adnate or attached by the base, the 

 branches growing erect and free, composed of lobes 

 which are dichotomonsly divided, slightly expanded and 

 usually bifid at the extremities, of a purplish colour, 

 vitreous and punctate, the dorsal surface striated lon- 

 gitudinally. Zocecia disposed on the branches in promi- 

 nent, oblique, semialternate series, more or less curved 

 outwards above, usually connate, sometimes free to- 

 wards the extremities, the cells in each series increasing 

 in height from the outer side iuAvards. 



Var. a (radiaia). Zoarium regularly radiate in form, 

 attached by a central disk, the branches disposed round 

 it, free and suberect, generally bifid at the extremities. 



This species varies much in appearance according to its 



