DESCRIPTIONS OP SPECIES. 173 



This is a very well characterized species. It seems to have its 

 closest resemblance with Balanopliyllia irrorata (Conrad); V)ut that is not 

 great. The cost£e are much finer in the former than in the latter, and con- 

 stitute one good diiference. 



Balanophyllia pondeeosa sp. nov. 

 PI. XX, flgs. 1 to 2. 



A large, coarse species. Form elongate, cross section elliptical, curved 

 in plane of longer axis of the calice. Area of attachment rather large. The 

 size does not always increase uniformly from the base; therefore there are 

 sometimes girdling constrictions, giving the specimens a moniliform appear- 

 ance. 



Corallum wall composed of two layers, an outer rather thin, solid 

 one, and an inner, thick, vesicular. Viewed from the outside it looks solid; 

 it does not show perforations. The costse are low, broad, rounded, and 

 granular. There are larger costse, intervening between each pair of which 

 are either thi-ee or seven smaller ones. There aie five complete cycles of 

 septa. The costse corresponding to the first and second cycles are larger 

 than those corresponding to the higher cycles. In one system there are 

 two costse corresponding to septa of a sixth cycle. The total number of 

 costse is 98. Thin pellicular epitheca present. 



The number of septa have already been stated — five complete cycles 

 and occasional members of a sixth cycle. Those of the fifth cycle fuse in 

 front of the included fourth. The septa are very thin, and have spinose 

 sides. Columella large vesicular. The calicular portion is so broken that 

 as good measurements as were desired could not be obtained, but those 

 obtained were as follows: Greater diameter of calice, 25 mm.; lesser 

 diameter of calice, 20 mm. ; height, 44 mm. 



Locality. — Prainc Creek, Wilcox County, Alabama. (L. C. Johnson, 

 collector.) 



Geologic occurrence. Mldway bcds. 



Type. — United States National Museum. 



This species may be easily distinguished by its large size, moder- 

 ately large ai-ea of attachment, thin outer solid wall, thick inner vesicular 

 wall, and low, wide, round, granular costse. It seems nearer to B. elongata 

 or B. caulifera than to the other species of the genus, but both of these 

 species are much smaller and have very small areas of attachment. 



