44 BULLETIN 9(3, UNITED STATES NATIONAL MUSEUM. 



versely. The lower face is smooth and presents some Uirge, scat- 

 tered concavities. 



f^«=0.10 mm. 

 Measurements. — Aperture w^_q xi_o.12 mm. 



r/,.2= 0.60-0.70 mm. 

 2of^"«|7,"=0.40mm. 



Variatiwis. — In longitudinal section we are better able to com- 

 prehend the organization of this species. In particular the dorsal 

 Avail is a very thick olocyst, the cavities observed on the exterior do 

 not perforate it; they limit the zotecia between which they are 

 hollowed out. The large frontal pores open into the same zooecia ; 

 the tremopores are tubules; finally, the avicularium is a very large 

 chamber hoUoAved in the thickness of the frontal wall. 



Occurrence. — Yicksburgian : West bank of Conecuh Eiver, Escam- 

 bia Countv. Alabama (common). 



Type.— C^ii. No. 62592, U.S.N.M. 



Fourth Group. MICROPORELLAE. 



Genera of this group are not represented in the Early Tertiary. 



DIVERS GENERA. 



The genera listed under this heading have some peculiar characters 

 which do not permit of their classification in any of the large groups 

 cited ; but they appear really to belong to the same general family. 



The principal genera, Avith their ranges and American occurrence 

 (marked *) are: 



* Hou2eauina Pergens, 1889. Jacksonian, Priabonian. 



*CycUc'opora, Hincks, 1884. Jacksonian-Eecent. 



Kymella, ncAv genus. Recent. 



Anarthropora Smitt, 1867. Latdorfian-Recent. 



*Alimdosia Jullien, 1888. Wilcoxian-Recent. 



KYMELLA, new genus. 



{Kyma^ undulation, in allusion to the undulated form of the proxi- 

 mal border of the operculum.) 



The hyperstomial ovicell is always closed by the operculum. The 

 frontal is bordered laterally by areolae. The aperturu bears a very 

 wide rimule. 



Genotype. — Kymella {CycUcopora) polaris Waters, 1904. Recent. 



STOMACHETOSELLIDAE, new family. 



The frontal is thick and occasions the formation of a peristomie. 

 The apertura is generally orbicular or semilunar with a very con- 

 cave proximal border. The peristomice is ahvays different in form ; 



