262 



MOLLUSCOIDEA BRYOZOA 



SUB-KINGDOM V 



Family 3. Idmoneidae. Busk. 



Zoaria forming free or adnate, variously compressed branches. Zocecial apertures 

 rounded, more or less elevated, usually arranged in transverse rows on two faces of the 

 branches ; sometimes the two faces are confluent. Dorsal surface of the branches without 

 zocecia, but often occupied by numerous small tubular pores, which may also occur near the 

 apertures. Sac-like ovicells with but a single opening. Ordovician to Recent. 



Idmonea, Lam. (Reptotubigera, Crisina, d'Orb.), (Fig. 416). Repent or erect, simple 

 or branching. Branches usually triangular, two of the faces carrying the zocecial 



apertures, which are generally 

 arranged in alternating transverse 

 series. Jura to Recent. 



Bisidmonea, d'Orb. Quadrate, 

 simple, or branching stems, bear- 

 ing zocecial apertures on all faces. 

 Cretaceous. 



Filisparsa, d'Orb. Branches 

 compressed dorso-frontally ; aper- 

 tures irregularly disposed ; other- 

 wise like Idmonea. Cretaceous. 



Filicavea and Filicrisina, 

 d'Orb. Cretaceous. 



Hornera, Lam. Zoaria with 

 side, highly N.Y. 'Branches of a ffee op anaatomosing| gene rally 



sub-cylindrical branches. Zooecial 

 apertures more or less irregularly distributed. Cretaceous to Recent. 



Reticulipora and Retecava, d'Orb. Zoaria reticulated ; branches greatly compressed 

 laterally. Cretaceous. 



Bicrisina and Sulcocava, d'Orb. (Laterocava, d'Orb.) Cretaceous. 



Protocrisina, Ulrich (Fig. 417). Narrow, bifurcating branches, celluliferous on one 

 side only. Zocecia sub-tubular, with prominent circular apertures arranged in inter- 

 secting diagonal series. Small pores, apparently communicating with interior of the 

 zocecia, irregularly distributed over both faces of the branches. Ordovician. 



FIG. 416. 



Idmonea dorsattt, Hagw. Upper Cre 

 taceous ; Maestricht. A, Branch, 



3r, and C, Lower 

 niagn 



FIG. 417. 



Protocrisina exigua, 

 Ulrich. Trenton 

 Group ; Trenton, 

 N.Y. Branches of a 

 large expansion, 1%. 



Family 4. Entalophoridae. Reuss. 



Zoaria ramose ; branches free, sub-cylindrical, with rounded and more or less promin- 

 ently exserted zocecial apertures opening on all sides. 

 (?) Without accessory or interstitial pores of any kind. 

 Ordovician to Recent. 



Entalophora, Lam. (Pustulopora, Blv.), (Fig. 418). 

 Zocecial tubes disposed about an imaginary axis, and 

 with rounded, more or less prominent apertures. Jura 

 to Recent. 



Spiropora, Lam. (Laterotubigera, d'Orb.), (Fig. 419). 

 Like the preceding, but apertures arranged in regular, 

 spiral, or transverse linear series, and closely situated. 

 Zocecial tubes disposed about a definite central axis or 

 axial tube. Jura to Recent. g ula^H g\v. 



Mitroclema, Ulrich, Ordovician ; Clonopora, Hall, Planer ; Plauen, 

 Devonian ; Peripora, d'Orb., Cretaceous. 



Diploclema, Ulrich. Similar to Entalophora, but with branches spreading in the 



FIG. 418. 



FIG. 419. 



Spiropora ver- 

 ticillata, Goldf. 

 Upper Cretace- 

 ous ; Maestricht 

 (after Hagenow). 



