ILLUSTRATIONS XI 



Ohdovician tkit.obitbs of the family Telephidab and conceened 

 stkatigraphic correlations 



By E. O. Ulrich 



Facing page 

 I-S. Ordovichm trJlobites of the family Telephidae 90-98 



MiTEOSPIKA, A NEW OkDOVICIAN GASTEROPOD GENUS 



By Edwin Kirk 

 .1-3. Mitrospira longwelli, a new genus aiid species 6 



A NEW FOSSIL COBAL FROM THE CEETACEOUS OF TEXAS 



By J. Edward Hoffmeister 

 1-2. Cretaceou:-: corals from Texas 4 



A NEARLY COMPLETE CARAPACE OF A FOSSIL TURTLE, AmYDA VIRGIN- 



lANA (CIARIC) 



By W. Gardner Lynn 



1. Nearly complete carapace of Avvyda virglniana (Clark) 4 



2. Fragments of costal, plate of Atni/da virglniana (Clark) 4 



TEXT FIGURES 

 North America?? species of the wesvils of the Otjorhynchid 



GENUS MeSAGROICUS 



By L. L. Bucbanan 



Page 

 1. Distribution of species of Mesagroicus in the United States 3 



BrIAROSACCUS CALLOSUS, a new genus and NEW SPECIES OF A 

 RhIZOCEPHALAN PARASITE OF LITHODES AGASSIZII SmITH 



By H. Boscluna 



1. Briarosaccus callosus, right surface 2 



2. Briarosaccus callosus, part of the mantle, with the mantle opening 3 



3. Briarosaccus callosus, the greater part of the mantle, internal surface- 3 



4. Briarosaccus callosus, visceral mass, riglit surface 4 



5. Briarosaccus callosus, part of a transverse section b in Figure 4, 



showing the testes, X7 4 



6. Briarosaccus callosus, part of a transverse section, a in Figure 4, show- 



ing one of the colleteric glands 5 



7. Briarosaccus callosus. a, section through the mantle showing the two 



layers of the external cuticle, the internal cuticle, and the epi- 

 thelium, muscles, and lacunae of the mantle, X18. b, excrescences 

 of the external cuticle, seen from above, X660 7 



8. Briarosaccus callosus, retinacula. a, part of tlie internal cuticle with 



retinacula, X45. b, c, and d, three different retinacula, X330 8 



