FLORIDAN BRYOZOA. 15 



and more takes the appearance of Discoporella denticulata, Gabb et Horn 1 ). The smal- 

 ler pores then disappear, or, instead of them, only a few greater ones are to be seen, 

 irregularly distributed; and, on some zooecia of the same colony, the whole calcifica- 

 tion of the front side only appears as narrow ribs between the greater pores, connec- 

 ting a central plate with the margins of the zooecia. If that central plate be thrown 

 away, the margins of the area appear dentated, through the rests of the named ribs. 

 In that state we recognize the figures of Cupularia denticulata given by Busk 2 ). 



Through the last remarks, we may easily understand the relation of this form 

 to the Cupularia döma 3 ) (Pl. III, figs. 81 — 84), which is much more highly calcificated, 

 immediately from the beginning of the colonial growth, whereby this acquires its more 

 conical form (figs. 83 and 84). At the same time, the zooecia grow higher, in raising 

 their sidewalls, whereby their secondary front-side appears to be more deeply immersed. 

 The warts, also, on the back side of the colony, grow higher, sometimes giving this 

 side that appearance of being aculeate, as remarked by D'Orbigny. Now, all these cha- 

 racteristics are more and more approximated by the variations of the preceding form; 

 and I can-not but regard the Cup. döma as the most highly calcified variety of the 

 Cup. umbellata. 



Pourtales has taken two colonies of Cup. döma from the depth of 29 fathoms, 

 at Florida. In the same cast he took three colonies of Cup. umbellata, what form he 

 found, also, at the depth of 7 fathoms, off Cape Fear-River. Through the kindness of 

 Mr. Busk, I have been enabled to compare these with his Cupularia Johnsoni, which 

 was taken, by the Porcwpme-expedition, from a depth of 45 fathoms, off Algeriä. 



With a structure, which reminds us, through its most important characters, of the 

 preceding genera, here I propose to be placed, provisionally, a new generic division, 

 which I name Steginoporella, thus characterised: 



Zooecia flustrina, extus microporidacea, intus calcificatione secundaria constru- 

 ctionem Steginoporarum (D'Orb.) imitantnr. 



Steginoporella elegans 4 ) (Pl. IV, figs. 96 — 101). 



This species, in Membraniporella — growth as well as in Siphonella (fig. 101) — and in 

 Eschara (fig. 100) — growth, was taken by Pourtales at the depths of 15 — 37 fathoms. 



In its outer appearance (fig. 96), with the ectocyst preserved, it already is de- 

 scribed and excellently figured by Busk; but the inner structure of its zooecia seems 

 yet to be noticed only by M. Edwards, inasmuch as it is described by him in a worn 

 condition. 



l ) Monogr. Sec. Tert. Foss. Polyz. N. Åmer., Journ. Acad. Nat. So. Philad., N. Ser., vol. V, Art. III, p. 



142, pl. 20, fig. 25. 

 -) Urag Polyzoa, p. 85, pl. XIII, fig. 1. 

 ;i ) Discoflustrella döma, D'Orb., Pal. Franc, 1. c, pag. 561. 



Cupularia Johnsoni, Busk, Quart. Journ. Micr. Se, vol. VII, p. 67, Zooph. pl. XXIII, figs. 1 — 5. 

 ') Eschara elegans, M. Edw., Ann. d. So. nat., ser. 2, vol. VI, p. 337, tab. 12, fig. 13; D'Orb. (Escha- 

 rellina) Pal. Franc, Terr. Crét., vol. V, p. 448. 



Obs. Nomine generis Escharellina usus essem, si eum nomine Escharinella non tam faeile confundi 

 posset. 



Membranipora magnilabris, Busk, Cat. Brit. Mus., Polyz., p. 62, tab. LXV, fig. 4. 



