SCHIZASTER CANALIFERUS. Gil 



forming an outward angle near its extremity ; it runs diagonally from the 

 extremity of the lateral anterior ambulacra to the termination of the porif- 

 erous zone of the odd ambulacrum. The fasciole is broadest at the extremity 

 of the anterior lateral ambulacra, and where it crosses (at right angles) the 

 odd ambulacrum. The lateral fasciole is narrow ; it commences from the 

 angle of the posterior lateral interambulacra, runs diagonally across the test 

 to the level of the lower edge of the anal system, where it descends rapidly, 

 forming an angular loop below the anal system, the lower extremity of which 

 nearly reaches the actinal plastron. The anal system is pointed, longitudi- 

 nally elliptical ; the whole of the abactinal surface is crowded by minute, 

 uniform, secondary tubercles, with flat scrobicular circles; the edge of the 

 anterior groove carries somewhat larger tubercles, and below the fasciole the 

 tubercles of the anterior part of the test increase rapidly in size towards the 

 ambitus, becoming larger and more distant as they approach the actinostome ; 

 the same is the case in the lateral posterior ambulacrum ; the tubercles, how- 

 ever', increase more gradually, and on the posterior extremity they do not 

 attain so great a size. The tubercles of the actinal plastron increase very 

 gradually in size towards the actinostome from the posterior edge ; they are 

 closely arranged in rows, diverging, fan-like, from the posterior edge towards 

 the actinostome, forming, at the same time, indistinct rows, diverging fan- 

 like from the central line of the elongate actinal plastron, with its rounded 

 sides, slightly narrower at the posterior extremity. The bare ambulacral 

 avenues are narrow ; the phvllodes not very prominent ; the posterior lip 

 of the actinostome raised, pointed, with a lip turned back. 



The spines of the abactinal surface are short, slightly curved, somewhat 

 club-shaped at the end, slightly longer on the edge of the petals, which they 

 cover completely, and also reach across the deep, broad anterior groove. 

 On the actinal side they increase in length in proportion to the size of the 

 tubercles, forming a pointed tuft over the anal system, and U\o lateral tufts, 

 on each side of the extremity of the actinal plastron. The spines at the 

 extremity of the actinal plastron are cupped at the end. 



The color of dried specimens is silver-gray. Usually two large genital 

 openings. 



