C1U15KII INA UADIATA. 185 



depends on the primary composition of the cell-wall, and 

 indicates the course of its development. The ridges radi- 

 ating towards the centre represent the rib-like processes 

 given off from the margin of the young cell, as in the 

 genus Membramporella, which ultimately meet and form 

 a protective covering. These ridges are united laterally 

 by outgrowths of stony matter occurring at intervals ; 

 and the spaces between the connecting links are repre- 

 sented by the interstitial punctures of the adult organism. 

 So that the genus is founded not on any trivial peculia- 

 rities, but on the essential structure of the cell itself. 



Cribrilina marks a transitional stage in advance of that 

 represented by Membraniporella. 



A considerable number of fossil species are known, 

 some of which reach back to the Cretaceous deposits. 



CRIBRILINA RADIATA, Moll. 



Plate XXV. figs. 1-9. 



!]-< IIAUA K.VDIATA, Moll, Seerindo, 63, pi. iv. fig. 17. 



LKI-KALIA INNOMJNATA, Couch, Corn. Faun. iii. 114, pi. xxii. fig. 4 (worth- 

 less) : Johnston, Br. Z. ed. 2, 319, pi. Iv. fig. 12 : Busk, 

 B.M. Cat. u. 79, pL boom. figs. 2, 3: id. Crag PoL 40, 

 pi. iv. fig. 2: Hincks, Devon and Corn. Cat, Ann. N. II. 

 ser. 3, ix. 203 (p. 43 sep.) : Manzoni, Suppl. Bryoz. Medit. 

 prima Contr. 4, pi. i. fig. 5 (Sitzb. k. Akad. d. Wisaenscb. 

 Bd. Ixiii. 1. Abth. Feb.-Heft, 1871); Bryoz. Pliocen. Ital. 

 prima Contr. 8, pi. ii. fig. 13 (Crag form). 



? I'U-STKA I'OUILLETII, Audouui, Savigny, Egypte, pL ix. fig. 12. 



? LEFKAUA MCLTIKADIATA, Reuss, Oberburg, 31, pi. x. fig. f> ; Palaontol. 

 Studien, ii. 43. 



LKPKALI A SCHIITA, Iteu&n, Sitzungsb. k. Akad. d. Wissensch. Bd. 1. 28, pi. xv. 

 fig. 3 ; Bryoz. d. dcutscb. Septaricntb. 18G( '.. | n.ra), 



Polyp, d. Wiener Beckens, 82, pi. ix. fig. 24 : Matuotii, 

 Suppl. SLC. 't, pi. i. fig. 6. 



Li.ruu.iA PRITIOHA, Rents, Hrj-oz. d. deutacb. Septarientli. ."'.' pi \n 

 fig. 4. 



1.1 1-KAL1A CALOMOKPIIA, KttUS, I. C. 62, pi. XI. fig. ll'. 



