EAELY PALEOZOIC BRYOZOA OF THE BALTIC PEOVINCES. 297 



The internal structure is simple, although very characteristic for 

 the genus. In tangential sections the angular zooecia and mesopores 

 with their thick walls bearing rather small acanthopores are to be 

 noted. Vertical sections show thick, well developed, incomplete dia- 

 phragms in the mature region, with tliin, flexuous walls and no dia- 

 phragms in the immature zone. 



Excepting HemipTiragma maculatuTn, this species differs from all 

 others of the genus in its very slender, ramose zoarium. The internal 

 structure is somewhat similar to that in H. panderi, but the latter has 

 a stouter zoarium with smaller zooecia, fewer mesopores, and more 

 numerous acanthopores. The specific name is in honor of Dr. F. A. 

 Bather, who collected the type-specimens. 



Fig. 182.— Hemipheagma batheri. a and 6, two fragments, natural size; c, a tangential section, 

 X20, sho"«t:ng the characteristic, thick- «valled, polygonal zocecia; d, vertical section of a 



BRANCH, X20, exhibiting CHARACTERISTIC TABULATION. CHASMOPS LIMESTONE, SOUTH OF BODAHAMN, 

 ISLAND OF OELAND. 



Occurrence. — Not uncommon in the Chasmops limestone, south of 

 Bodahamn, island of Oeland. 



The figured types and sections are in the collections of the British 

 Museum. 



Genus ANAPHRAGMA Ulrich and Bassler. 

 Anaphragma Ulrich and Bassler, Smiths. Misc. Coll., vol. 47, 1904, p. 49. 



This genus was estabhshed for a species agreeing in all respects with 

 Batostoma Ulrich, save that the zooecial tubes and mesopores were 

 practically free of diaphragms, and that the walls in the inimature 

 region were strongly crinkled. Up to this time but a single species 

 was known, Ana'phragma mirabile from the Fernvale Hmestone of the 

 Richmond group in Illinois and Wisconsin. 



Genotype. — Anaphragma Tnirdbile Ulrich and Bassler. Early 

 Silurian (Richmond) of Ilhnois, WisconsiUj and Esthonia. 



