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Gregorv ') has criticized the reference of recent species to the genus Lichenopora. He 

 points out that of the three species originally included in Lichenopora by Defrance, L. turbi- 

 nata -), an Hocene species, was definitely selected as the genotype by D'Orbigny 3 ), and that 

 in this species the orifices are "in elliptical radial bundies, and not in single radial lines". 

 Recent species which have the latter arrangement are thus wrongly referred to Lichenopora, 

 and should be placed in Discocavea D'Orbigny; or perhaps (p. 233) in Melobesia Lamx or 

 Disporella Gray, altered by Busk to Discoporella. Pergens 4 ), on the other hand, considers that 

 recent species agree in their general characters with L. furbinata, the genotype of Lichenopora. 



I do not feel convinced that the arrangement of the zooecia in radial lines or otherwise 

 can be adopted conveniently for the generic separation of recent species. These are greatly 

 in need of further revision ; but the number of species considered in this Report is insufficiënt 

 for that purpose. It may, however, be pointed out that of the three species here described, 

 the lïrst has its zooecia in strongly marked radial lines, which have either uniserial or biserial 

 zooecia; the second has most of its zooecia disposed quincuncially ; while in the third the 

 zooecia might be described as being arranged in biserial elliptical groups. These facts may 

 indicate that more than one genus is represented ; but I do not feel able to attempt to arrange 

 the recent species according to this character. It appears to me probable that a comparative 

 study of the ovicells might gïve better generic distinctions ; and I may refer in particular to 

 the great difference, indicated below, between L. verrucaria and L. novae-ze/andiac in the 

 mode of development of the ovicells. It seems to me best, therefore, to leave the recent 

 species provisionally in Lichenopora, until some satisfactory method of grouping them can be 

 shown to exist. 



The following notes may be added with regard to the generic names which, according 

 to Gregory, are available for the recent species : — 



(1) Melobesia Lamx, 1S12. — Although, as Gregory points out (p. 233) L. radiata 

 was referred to Melobesia by Audouin in describing Savigny's figures, it is clear from the 

 descriptions and figures given by Lamouroux that M. pnstulosa 5 ) was a Calcareous Alga ; 

 and indeed Lamouroux gives Corallina as a synonym of J\Lelobesia. 



(2) Disporella Gray, 1848°). — The only species included in this sub-genus was 

 Discopora hispida Fleming, a common British species which is generally included in L^ichcnopora 

 by writers on recent Polyzoa. It is true that Disporella was given by Gray as a subdivision 

 of T7ibitlipora\ but- Gregory's criticism (p. 234) that it was not used in a generic or subgeneric 

 sense does not seem to me convincing. Disporella might thus be available if D. hispida and 

 its allies should be proved to deserve generic separation. 



1) Gregory, J. W., 1909, "Cat. Foss. Bry. Brit. Mus.", "Cret. Bry", II, pp. 247, 233. 



2) DEFRANCE, t. cit., p. 257, Atlas, PI. XLVI, figs 4 — 4/1 (reproduced in de Blainville, 1834, '•Man. d'Actinol.", PI. LXVIII, 

 figs 4 — 4/1. The zoarium of L. turbinata has the form of a funnel, atlached by its stalk-like narrow end, and terminated by a discoidal 

 snrface hearing the serially arranged orifices and numerous cancelli. 



3) D'Orbigny, 1853, t. cit. p. 963. 



4) Pergens, E., 1889, t. cit., p. 379. 



5) Lamouroux, 1816, "Ili.-t. Pol. Cor. Flex.", p. 315. PI. XII, fig. 2; hettev figured in 1821, '■Exp. Method.", p. 46, 

 PI. LXXIII, figs 17, 18. 



6) Gray, .1. E., 184S, 1. cit. 



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