XX LIST or ILLUSTBATIONS. 



Page. 

 Fig. 204. Hallopora goodhuensis. a, tangential section, X 20, of a small speci- 

 men; h, vertical section of the same specimen, X 20 328 



205. Hallopora wesenbergiana. a, tangential region, X 20; h, tangential 



section, X 20; c, vertical section, X 20, showing characteristic 

 tabulation 328 



206. Hallopora splendens. a, fragmentary specimen, natxiral size; &, tan- 



gential section, X 20; c, usual aspect of tangential sections, X 20; 



d, vertical section, X 20; e, another vertical section, X 20 330 



207. Hallopora dumalis. a to c?, view of four representative fragments, 



life size; e, surface of the slender specimen, X 9;/, stu-face of 

 another specimen, X 18; g, vertical section, X 18; h, tangential 

 section, X18. (After Ulrich.) 331 



208. Hallopora undulata. a and h, typical specimens of the natural size; 



c, surface of original of figure 6, X 9; <?, vertical section, X 18. 

 (After Ukich.) 332 



209. Hallopora toUi. a, small fragment, natural size; 6, tangential section, 



X 20; c and d, two portions of a vertical section, X 20, exhibiting 

 tabulation 333 



210. Hallopora elegantula. a, tangential section, X 18; 6, transverse 



section, X 18; c, tangential section, X 20, through the mature zone; 

 (7 and e, two vertical sections, X 18 and X 20, showing slight differ- 

 ences; /, surface view of several zooecia, X 20 335 



211. Hallopora ? dybowskii. a, tangential section, X 20, with zooecia, less 



angular than usual; 6, vertical section, X 8, showing curved 

 diaphragms; c, several tubes of the same, X 20 336 



212. Hallopora ? dybowskii. a, side view of a small example, natural 



size; h, basal view; c, an average tangential section, X 20; d, ver- 

 tical section, X 8; e, portion of the same, X 20; /, a long vertical 

 section, X 8 337 



213. Hallopora ? tenuispinosa. a, an ordinary fragment, natural size; 



h, tangential section, X 20; c, portion of the same, X 35; d, vertical 

 section, X 20; e, portion of a transverse section, X 20 339 



214. Archeopora lamella. Eichwald's views of his type-specimens, one 



(a and h, natural size and enlarged) showing mesopores, and the 

 second (c and d) apparently with solid interzocecial spaces 340 



215. Archeopora angulosa. a and h, the incrusting type-specimen, natural 



size and enlarged, showing angular zooecia and open mesopores. 

 (After Eichwald.) 341 



216. Archeopora punctata, a and h, the type-specimen, nattiral size and 



enlarged. (After Eichwald) 341 



217. Archeopora radians, a and h, the type-specimen, natural size and 



enlarged. (After Eichwald) 342 



218. Calamopora reticulata, a and h, zoarium natural size and surface 



enlarged. (After Eichwald) 343 



219. Dianulites apiculatus. a to d, four views of Eichwald's type of 



Chaetetes apiculatus; e, celluliferous sxnface enlarged. (After 

 Eichwald.) 344 



220. Micropora rhombica. Fragment of zoarium, enlarged. (After 



Eichwald.) •- 345 



221. Myriolithes fastigiatus. a, the type-specimen, natural size and 



slightly enlarged. (After Eichwald.) 346 



