108 • PROCEEDINGS OF THE ACADEMY OF [1889. 



3. Oulactis fasciculata. n. sp. (PL VI, fig. 5.) 



By this name I denote three specimens in various degrees of con- 

 traction, the largest of which measured about 1 cm. in height and 

 1-2 cm. in breadth. The color, as ascertained from alcoholic speci- 

 mens, is in the lower part of the column a grayish-brown similar to 

 what is frequently seen in preserved Actininse, while the upper part 

 of the column and the fronds are of a grass-green, the tentacles re- 

 sembling somewhat the lower part of the column, but having a dis- 

 tinctly greenish tinge. 



The column is provided in its upper part with about 48 vertical 

 series of tubercles, probably verruca?, there being about five or six 

 in each series, and is thrown into numerous transverse folds the re- 

 sult of contraction. The mesogloea, when exposed, appears to be 

 raised into numerous minute elevations, whereby the surface acquires 

 a finely punctured appearance. 



The tentacles are moderately long, simple and pointed at the ex- 

 tremity. They appear to be arranged in two cycles, and from a 

 necessarily uncertain count I estimate their number to be about 

 forty-eight. Their ectodermal longitudinal muscle layer is well de- 

 veloped, being arranged on long slender mesogloeal processes. The 

 fronds (PI. VI, fig. 5, fr.) are small, yet occupy the entire width of the 

 area between the tentacles and the apparent margin. They consist 

 of hollow evaginations of the disc, arranged in bunches. I could not 

 determine with certainty their number in any of the specimens, but 

 there are probably twenty-four of them in all. A well-defined 

 margin is present. 



Immediately external to the bases of the tentacles, and lying be- 

 tween them and the fronds there is an endodermal sphincter (sp.) 

 fairly well developed. Immediately external to it, in the region oc- 

 cupied by the fronds and for a slight distance down the column-wall 

 below the margin, there are no muscle processes, but further down 

 they do occur, forming what might be termed a second sphincter, 

 though it is by no means well developed. The surface of the disc 

 between the tentacles and the mouth is deeply depressed so that a 

 fosse is formed around the peristome. The mouth is large. Sec- 

 tions show that over the general surface of the stomatodreum the 

 mesogloea is very thin, and upon the ectodermal surface gives rise 

 to numerous more or less regularly arranged fine processes over which 

 the ectoderm passes so as to be thrown into numerous folds. The 

 gonidial grooves are deep, and are prolonged some distance below 



