88 NEW YORK STATE MUSEUM 



Jaekel refers a second species, E . b u c h i a n u s Forbes sp. 

 (from Bather's ms.) to Edrioaster, basing his generic description 

 on both forms. He describes the body as spherical from the cast of 

 E. buchianus. E. saratogensis appears as a low 

 spherical segment, but there is evidence of a flattening of the body 

 in the pushing of plates over each other, and since the underside is 

 not preserved in our material, it is possible that E. sarato- 

 gensis also was originally spherical. 



The direction of the spiral course of the^ ambulacra was in E. 

 saratogensis apparently already fixed in distinction to E . 

 b i g s b y i , where it could be solar or contrasolar ; and it has 

 already reached the condition of the ambulacral rays of Agelacri- 

 nites. 



The anal pyramid of E . buchianus is, according to 

 Bather, surrounded by irregular plates. Also in this character 

 E. saratogensis would seem to have advanced somewhat 

 in showing a regular pyramid. 



We have seen nothing that could be recognized as a madreporite. 



All three known species of Edrioaster are of approximately the 

 same age. 



Taeniaster schohariae nov. 



PI. 3, % i 



This interesting species of Paleozoic Ophiuroidae or brittle stars, 

 is based on a single individual, retaining three arms, one of which 

 presents the ventral view and the other two their lateral views, 

 resp. sections. The specimen is small, the arms about 15 mm 

 long, and it is without a disk. The arms are slender and flexible, 

 about 1.3 mm, wide at the base, and almost as high in lateral view, 

 originally probably cylindrical. The ventral view shows a straight 

 or slightly zig-zagged ambulacral canal, and on both sides of this 

 squarish depressions surrounded by the ambulacral and adambu- 

 lacral ossicles, the covering lower arm plates not being retained if 

 they existed. The inner (ambulacral or vertebral) ossicles appear 

 as narrow and outwardly curved ridges, the outer or adambulacral 

 ossicles as ridges bent in the opposite direction with a projection 

 in the middle of the outer arch. The ambulacral ossicles are not 

 directly opposite nor regularly alternating, but those of the right 

 side on the ventral view advanced about one-third the length of the 

 ossicles beyond those of the other side. 



