FLORIDAN BRYOZOA. 55 



well as in tubiform convolutions, at a depth of 60 fathoras, Pourtales has taken SW. 

 of Tortugas. 



In the ordinary form of the zocecial aperture, such as it already is well described 

 by Norman, it has its nearest correspondence in the typical constitution of Gemellipora. 

 In the young zocecia (fig. 165) we find the proximal margin of the aperture concave 

 or broadly sinuated, with a sinus at each side of it, proximally of the denticle at the 

 articulation of the operculum 1 ). In the older zocecia, the median sinus is narrower 

 and the lateral sinuses, commonly, are more marked, with a more pointed denticle at 

 the opercular articulation. This form of the zocecial aperture, indeed, would not give 

 us reason enough for placing it in the genus Escharella; but the greatly developed 

 primary pores on the front side of the zocecia give it an appearance, very alike to the 

 forms, which I have described under the collective name of Escharella porifera, and, 

 among the ordinary zocecia, whose aperture has a breadth of about 0,15 mm., we find 

 some greater ones, irregularly distributed (fig. 164, above, on the left in the figure), 

 whose proximal margin of the aperture, between the lateral sinuses, is projecting in 

 the form of a broad denticle. This more usually, judging from the figures given by 

 Norman, in the ordinary zocecia, also, seems to be the case in the European form of 

 this species. 



The avicularia, of an acute form, in the same manner as in Hippothoa spongites 

 and Escharella linearis, are very varying in their place, number and size. Sometimes 

 they are raised into high tubercles, sometimes they are low, horizontal and of small 

 size, and, then, amidst the great zocecial pores, they are very easily overseen. Their 

 most normal place seems to be that of one at each side of the zocecial aperture. 



The ocecia are already described by Norman. 



The overgrowing layers (the new layers of zocecia, growing över the older ones) 

 present the usual propensity of the zocecia to more and more becoming Celleporine; 

 thus we may find them almost vertically raised in an utriculate manner, with the aper- 

 ture at the tip and with the sides verrucose by the uneven calcification över the in- 

 terstices between the primary pores. 



How nearly this species is related to the 



Escharella pertusa 2 ) 



will appear, already, from the supposition, enounced by Norman, that Busk\s figures, 

 pl. LXXVTII, figs. 1 and 2, were drawn from the E. sanguinea. The specifical charac- 



1 ) As this denticle verv often is less obvious than the proximal ones, it is good reason for identifying this 

 species with the Escharina (Cellepora) torquata (subtorquata) DOrb. 



2 ) Cellepora pertusa, Espek, Forts. d. Pflanzenth., part. 1 p. 149. Cellep. tab. X; Lmrx., Pol. Cor. Fle.v., p. 

 89; M. Edw. (Escharina) in Lam. Anka. s. Vert., ed. 2, vol. 2 p. 232; Johnst. (Lepralia) Brit. Zooph.. 

 ed. 2 p. 311, tab. LIV tig. 10; Gray, List Brit. Anim. Brit. Mus., part. 1 p. 119; D'Orb. (Cellepora) 

 Pal. Franc, Terr. öret., vol. V. p. 401; Busk (Lepralia) Brit. Mus. Cat. Polyz., p. 80, tab. LXXVII1. 

 tab. LXXIX tigg. 1 et 2; NoRJfAN, Quart. Journ. Micr. Se, n. ser., vol. VIII p. 222 (p. 11 sep.). 



Cellepora perlacea, D. Chiaje, Mem. su gli anim. s. vert., vol. 3 p. 37, tab. XXXIV figg. 4 et 6; 

 M. Edw. (Escharina) 1. c, p. 234; D. Ch. (Cellepora) Descr. Notom. Anim. s. Vert., vol. V p. 148, tab. 

 158 figg. 1-fi; Thomps. Ann. Mag. Nat. Hist.. vol. X p. 20; DOrb., 1. c., p. 400. 



