FOEMATIOITS AND FOSSILS OF SOUTH MAljrCHUillA 37 



North America, but the Manchurian species usually has smaller 

 dimensions, shallower cup, and a shorter stem. 



Formation and locality. — ^Upper Canadian, Santao formation : In- 

 the dark-gray banded limestones above the second tunnel, 1 mile 

 north, of Pen-hsi-hu, Liao-tung, Manchuria. 



Holotype.—V.S.'^M.. No. 83617. 



ANTHASPIDELLA DISCOIDALIS, new species 



Plate 27, Figures 3, 4 



Description. — Sponge moderately large, discoidal, flat, with a 

 short stem. Outer margin subacute or rounded. The entire upper 

 surface is marked by rather irregular but more or less radially ar- 

 ranged furrows, averaging 1.2 mm in diameter. Oscula rather few 

 and indistinct. A vertical section shows that the tubes in the walls 

 are continuous, running diagonally upward from the cup wall to 

 the outer margin of the specimen. 



Diameter of the specimen, 75 mm ; height, about 12 mm ; diameter 

 of the cup, about 15.5 mm. 



G omp arisen. — The discoidal shape, smaller cup, and rather ir- 

 regularly radiating, comparatively wider canal system, serve readily 

 to distinguish this from any of the known species. 



Formation and locality.— 'Loy^Qv Ordovician, Kangyao formation : 

 In the black banded limestones west of Shang-kang-yao, 3 miles 

 southeast of the Yen-tai colliery, Liao-tung, Manchuria. 



Eolotype.—U.^.'^M. No. 83618. 



ANTHASPIDELLA? PLANULATA. new species 



Plate 31, Figtjees 7, 8 



Description. — The entire specimen is disk-shaped with a very shal- 

 low and rather wide cup. The specimen is penetrated by more or 

 less confluent and comparatively regularly distributed small canals, 

 rarely more than 0.2 mm in diameter. At the top these small canals 

 are arranged radially, extending from the interior margin of the cup 

 to the outer margin of the specimen, and are spaced about eight in 

 2 mm of the length of each transverse row. A vertical section shows 

 that the part beneath the cup and cup walls is traversed by vertical 

 canals opening into the base as well as the sides of the cup. Com- 

 paratively few ciliated chamberlike cavities are found in the cup 

 walls. 



Height of specimen, 8.5 mm; diameter at the top, 74 mm; diam- 

 eter of cup at cup margin, 27 mm ; depth of cup, 4 mm ; average ver- 

 tical thickness of cup wall, 5.5 mm. 



This specimen is characterized by its disk shape and wide, shallow 

 cup. 



