TURBINAKI^ MESENTERIFORMES. 57 



Species 3G. Turbinaria gemmulata. 

 Turhinark gemmuhia, Verrill, Appendix to Dana's Corals and Coral Islands, 1st edition, 1875. 

 Manopora (jemmulaia, Dana, Zoophytes, 1848, p. 491. 



Mmiliporaf gemmulata, Milne-Edwards and Haime, Ann. d. Sci. Naturelles, 3' Zool., xvi. (1857) 

 p. 62 ; and Les Coralliaires, iii. (18G0) p. 214. 



Description.— CoxaWxim contorted and foliaceous. Folia in gracefully clustering clumps, 

 6 inches high, 2-3 • 75 mm. thick. Outer surface smooth, not wrinkled. 



CaUcles regular, scattered, " short subtubiform." Aperture slightly elUptical, 1-25 mm. 

 long, neatly 12-rayed. "The centre of the bottom (? columella) a short tliin line." 



Dana considered this species as a transition between Manoimm and Turbinaria; it is 

 claimed as a true Turbiuarian by Verrill in the Appendix to Dana's 'Corals and Coral 

 Islands.' Habitat not recorded. 



The only recorded specimen belongs to the Academy of Natural Sciences of Philadelphia. 



Group v.— TURBINARI.E MESENTERIFORMES. 



TJiose TurUnarians in which the edge of the cup curls up at more or less regular intervals to form open 

 cylinders, vr finger-shaped processes. Tlie intervening tracts of the margin grow out as more or less 

 liorizontal lobes, which again curl up to form new cylinders. 



Species 37. Turbinaria mesenterina. (PI. XV. ; PI. XXXII. fig. 10.) 



Explanaria mesenterina, Lamarck, Anim. s. Vert., ii. (181 G) p. 255. 



?Gemmipora mesenterina, Blaiinillc, Manuel, 1834, p. 387. 



Explanaria cinerascens, Ehrenberg, Korallenthicrc dcs rothen Meeres, 1834, p. 82 ; cf. Klunzmger. 



Non Turbinaria mesenterina, Milne-Edwards, Les Coralliaires, 1860, p. 166. 



Turbinaria mesenterina, Klunzinger, Korallenthicre des rothen Meeres, ii. (1879) p. 50, pi. vi. 



I)csa-iption.—CQT:a.\lixm a flat nodulated mass built up by an extending fringe of fronds, 

 which curve upwards and roll round to form short, thick cylinders ; margin of frond thick, 

 pierced by a conspicuous row of deep round holes, representing young calicles. 



Calicles tend to project on hemispherical eminences. Apertures circular, parallel ^v^th 

 the surface of the cccnenchyma, 2 mm. in tUameter. Septa 18 to 20 (22 to 24, Khmziuger), 

 very inconspicuous ; where a ridge-and-furrow system is developed, the former rim over the 

 margin of the calicle to descend vertically as thin ridges or septa round the large, deep 

 (1 to 1 • 5 mm.), cyUndrical fossa. The interseptal loculi not sharply marked off peripherally. 

 The columella is nearly flat and loosely spongy. 



The ccenenchynia appears granular, but is finely ecliinulatc. ^\-ith a well-developed but 



delicate ridge-and-fm-row system. 



1 



