FLORIDAN BRYOZOA. 13 



part of the Floridan colony, for the most of the zooecia, particularly the younger ones, 

 corapletely agree with Busks figures. 



The specics is taken by Pourtales on died shells and on Nnllipora from the depths 

 of 29 and 44 fathoms. 



The Mollian series, probably, can be followed to a great richness of species of 

 various forms of growth. Thus, for instance, we will probably find its congeners in 

 the neighbourhood of Semieschara ringens etc. by D'Orbigny; and, as a Cupularian growth, 

 perhaps the Selenaria maculata, Busk, may be joined with it. Even among the true 

 escharine bryozoa there are many, such as Lepralia spathulifera, who mind of the form 

 of its area; but there is mnch tö be done, before with certainty we can say anything 

 about that question. As the middle of the proximal margin of the zocecial area, as 

 well as its lateral tooth, of Mollia antiqua, very usnally raise themselves, we may 

 think they would meet each other, and thus the comparison of its structure farther 

 may be followed for the explanation of the structure and affinities of such forms as 

 Mollia holostoma '), M. oceani 2 ) and Steginoporella elegans (M. Edw.), what species will 

 be discussed further down. 



Such a raising of the distal part of the front side of the zooecia also gives the 

 character to a group, whose most simple species, by Gray 3 ), was the type for the family 



MICROPORID.E. 



The aperture, closed by its operculuin, in this family coincides with the distal 

 part of the margin of the zooecion, and proximally, at the articulation of the opercu- 

 lum, it is limited by a transverse rib, formed by the raising, in that line, of the front side. 

 Thus, in the full development of the type, the primary area, in the same manner as 

 on the Escharines, disappears; and as this was the most pregnant character of the sec- 

 tion Escharina, here, also, we perceive the close proximity of that group, although yet 

 the plain front side and the raised primary margins of the zooecia mind us of the 

 Flustrine nature. 



Micropora coriacea 4 ) (Pl. III, fig. 74). 



This species, as it of late years by Johnston, Gray and Busk d ) is determined, 

 without doubt in the European seas 6 ) is identical with the Floridan one. Pourtales 

 has taken it in very different depths, from 36 to 135 fathoms, growing on died shells, 

 Nullipora and stones. 



] ) Membranipora holostoma, Busk, Cray. Polyz., p. 36, tab. III, fig. 11. 

 -) ibid., p. 35, tab. III, fig. 8. 



:i ) Brit. Mus. Cat., part I, Rad., pages 115 and 147. 



4 ) An Escharina penwiana, D'Orb., Voy. cl. 1'Amer. mer., Polyp., p. 16, tab. VII, fig. 9 — 12? 

 •') Johnst. (Flustra) Brit. Zooph., ed. 2, p. 348, tab. LVI, fig. 8. 

 Gray (Micropora) Brit. Mus. Cat., part I, Bad., p. 115. 



Busk (Membranipora) Brit. Mus. Cat., Polyz., p. 57, tab. LXXIII, figs. 4, 5. 



Obs. The Flustra (Discopora) coriacea of Esper (Pflanzenth., Flustra, tab. "VII) seems better to agree 

 with Membranipora bifoveolata, Heller (Bryoz. Adr. Meeres, Verb., k. k. zool, bot. Ges. Wien 1867, pag. 

 95), if that form really should be distinct from M. coriacea. 

 ti ) Lepralia complanata, Norman, Ann. Mag. Nat. Hist., ser. 3, vol. XIII, pag. 84 (p. 4 sep.), tab. X, fig. 4. 



