NO. 1193. SOME NEOCENE CORALS— GANE. 195 



For a further detailed aud most elaborate description of this coral 

 consult the paper by Dr. G. J. Hiiide on the genus 8eptastr(va in gen- 

 eral, and the present species in particular. Nothing but the mode of 

 attachment is now added to the characteristics of the form as so clearly 

 determined by Dr. Hinde. 



The present writer, however, considers the Septastrcea forhesi Ed- 

 wards and Haime, as a synonym of the S. sexradiata Lonsdale. In 

 discussing the similiarity of the two species Dr. Hinde' ajjtly sum- 

 marizes the subject in the following words. He says that — 



It is very evident ttiat in form, mode of gi'owth, and in every other feature but 

 one, this species {S. se.xradiaia) is closely similar to Septastrwa forhesi . The one fea- 

 ture in which it differs is the greater development of the third cycle of septa within 

 the calices. 'J his feature, curiously enough, is limited to the calices, for in the lower 

 part of the corallites only the 12 septa of the first and second cycles are devel- 

 oped, as in S. forhesi, so that specimens in Avhich the surface features are partially 

 obliterated can not be distinguished from this latter species. I haA^e serious doubts 

 whether this one feature may not, after all, be due to a more favorable condition of 

 growth or environment to which this particular specimen has been exposed. It is 

 somewhat remarkable that of the thirteen specimens of Septastraa which have come 

 under my notice this is the only one which exhibits sucli a development of the third 

 cycle of septa in the calices; in alf others this cycle is only indicated by marginal 

 ridges. There is a considerable amount of variation in this respect in the specimens 

 referred to Septastraa forhesi, for in some only 6 septa are developed in the calices, 

 in others 12, and yet no siiecific distinction can be made, since in certain specimens 

 both conditions are present. It might therefore be urged that, as Lonsdale's speci- 

 men is undistinguishable in every other respect from Septastrcea forhesi, the difference 

 in this variable feature does not possess specific value. While admitting the force 

 of the argument, I think it is preferable provisionally to allow the difference to be 

 specific, and if further evidence should show that it must be regarded as merely 

 due to external conditions, and that there is only one species, then this species 

 must bear Lonsdale's name of sexradiata, since this has the priority of Edwards ai.J 

 Haime's name, forhesi. 



As the form under discussion is the most common coral occurring in 

 the beds of the Virginia Miocene, the writer has had an opportunity of 

 studying a large series of specimens, and has reached the conclusion 

 as stated above that all belong to the same species, although in tbe 

 superficial calices there is often a remarkable divergence in the rela- 

 tive development of the septa and the pseudocolumella. Were the 

 Septastrcea forhesi allowed of specific value, then a number of new spe- 

 cific names should be employed for these forms with calices, either con- 

 taining but 6 or less septa, or with the septa of the latter cycles united 

 with those of the preceding, or with the other similar modifications in 

 the calice. 



That both Mr. Lonsdale and Sir Charles Lyell considered these Sep- 

 tastrwa as of one species, the <S. sexradiata is evinced by the fact that 

 the former, who described the forms, gave but one specific name to them, 

 and the latter, who collected the specimens, stated^ that lying on the 

 beach of the James Kiver were masses of the 8. sexradiata upward of 



'Quart. Journ. Geol. Soc, XLIV, p. 220. 

 ^Idem., 1, 1845 p. 416. 



