124 MONOGRAPH OF THE FOSSIL TOLYZOA OF THE 



In 1840, Roomer gave to the Cellepora of Fabricius the names of Discopora and 

 Marginaria when the cellules were not convex, and Escharoides the species with con- 

 vex cellules, while he named Escharina, polyzoa entirely different from those of the 

 same name of M. Edwards, and which include the present genera Reptescharipora and 

 Replescharella of d'Orbigny. In 184?, Reuss placed the Celleporaz with the Mem- 

 branipora} under the name Discopora, and with Marginaria, which contained besides 

 many other distinct genera, while he placed in Escharina several genera entirely dif- 

 ferent from those of Edwards. In 1851, Hagenow returned to the genus as defined 

 by Fabricius, and placed as subgenera Escharoides, Dermatopora (which corresponded 

 to Membranipora of Blainville) and Marginaria, in the latter of which he placed be- 

 sides Membranipora and Escharina, which, like those of Roemer and Reuss, are en- 

 tirely different from Escharina of Edwards. D'Orbigny, in 1839, in the " Bryozoaires 

 de l'Amerique Meridionale," in 1847 in "Prodrome de Paleontologie Strat.," and on 

 some of the earlier plates of " Paleont. Franqaise," used Edwards' name Escharina for 

 Cellepora. 



The above will convey an idea of the apparently inextricable confusion into which 

 the subject seemed to have fallen, and we are certainly indebted to that most inde- 

 fatigable student Alcide d'Orbigny for setting it right. There is yet one point about 

 which he says nothing. He does not, as far as we are aware, once refer to the name 

 Lepralia of Johnston. This author, taking the many layered species to be the true 

 Cellepora:, in other words, following the Lamarckian determination of the genus, 

 founded a new genus, taking Cellepora hyalina, Linn., a common British species, for 

 his type, and called it Lepralia. 



We are not acquainted with this particular species, but after a careful study of all 

 the figures and descriptions at our disposal, not only of the typical species, but of all 

 the other Lepralia? , we cannot find a single point on which a generic division can be 

 based. 



C. tubulata, Lonsdale, Quart. Jour. Geol. Soc. vol. 1. p. 70, is apparently either a 

 Heteropora or a Multicrescis. Possibly it may prove to be the M. parvicella, G. and H. 



C. prolifica, G. and H. 



C. bilabiata, G. and H., Proc. Acad. Nat. Sci. 1860, p. 366. 



0. bilabiata, G. and H., Jour. Acad. Nat. Sci. 2d ser. vol. 4, p. 400, pi. 69, f. 21, 22. 

 Not C. bilabiata, Busk, 1854, Brit. Mus. Catal. 

 Colony encrusting, generally in elongated patches, composed of cellules arranged in 

 irregular quincunx and in pretty regular lines. Mouth large, anterior, round or trans- 

 versely oval, sometimes with the proximal lip straight : no thickenings or true lips. 

 Surface very convex,, elevated in the middle and slightly projecting towards the mouth, 

 which opens obliquely forwards. Ovarian vesicles numerous, short, convex, wider 

 than long and slightly emarginate at the oval margin. No surface markings were 



