EARLY TERTIARY CHEILOSTOME BRYOZOA. 25 



joined back to back and each pair arising from the anterior extremity 

 of the preceding pair. Opesia large, sloping slightly upward. 

 Ovicell? (Robertson.) 



Genotype. — Gemellaria lorieata Linnaeus, 1758. 



GemeJlaria yrima Eeuss, 18G8, has been identified in the Upper 

 Jacksonian of Alabama. 



Division 11. COILOSTEGA Levinsen, 1909. 

 (Opesiulae Julllen, 1888). 



The parietal muscles are attached to the ectocyst and traverse the 

 chitinous or partially calcified cryptocyst by means of the opesiules. 

 The hj^drostatic system is zoarial but each zooecium in addition is 

 provided with a hypostege with the cryptocyst calcified. 



The families of this division represented in the American Early 

 Tertiary are as follows: 



Opesiulidae Jullien, 1888. 



Subfamily Onychocellidae Jullien, 1881. 

 Subfamily Microporidae Hincks, 1880. 

 Subfamily Lunulariidae Levinsen, 1909. 

 Steganoporellidae Levinsen, 1909. 

 Thalamoporellidae Levinsen, 1909. 



Family OPESIULIDAE Jullien, 1888. 



The parietal muscles are attached to the cryptocyst ; their place is 

 indicated either by pores or by lateral indentations called opesiules. 

 The ovicell is endozocecial. 



Subfamily Onychocellidae Jullien, 1881. 



The ovicell is endozocecial. The parietal muscles are attached to 

 the ectocyst. The cryptocyst is calcified. The avicularia are inter- 

 zooecial and transformed into onychocellaria. 



This subfamily includes six genera, all of which are represented 

 by species in America : 



OnychoceUa Jullien, 1881. Bathonian-Recent. 



Rectonychocella, new genus. Jacksonian-Recent. 



Velimvella, new genus. Jacksonian-Recent. 



Diplopholeos^ new genus. Jacksonian, Vicksburgian 



FloridiTia Jullien, 1881. Senonian-Recent. 



Smittipora Jullien, 1881. Senonian-Recent. 



RECTONYCHOCELLA, new genus. 



The retractor muscles of the polypide are attached in the median 

 axis of the zocecia. The opesiular indentations are symmetrical. The 



