STRATA OF JAVA. 7*7 



terior pair of ambulacra. The test is very much flattened, 

 its edge swollen ; a strongly marked depression surrounds the 

 petals. They are long and of equal length , lanceolate , nearly 

 closed at the extremity. The pores , connected by distinct 

 grooves , are closely packed together ; there are five of them 

 in a millim. The abactinal system is small , five indistinct 

 ridges radiate from hence along the middle ambulacral 

 area. The basis is flattened or indistinctely concave. The 

 mouth is small and subcircular ; so is the anus , although 

 sometimes inconspicuously elongated in the direction of 

 the longitudinal axis of the test; its distance from 

 the border being about two or three times its diameter. 

 The ambulacral furrows are indistinctly developed and 

 extend about half the distance between the mouth and 

 the angles of the test. The peristomal star is still more 

 indistinct, sometimes even hardly visible. The primary 

 tubercles are equal in size on the superior and inferior 

 surface of the test and measure about | of a mm. ; on the 

 inferior surface they are at a greater distance from each 

 other , and on the border closely set. There are constantly fine 

 granules between them. Genital openings as in L. depressum. 



The pentagonal forms of this fossil are closely similiar 

 to the last named species , they may however be imme- 

 diately recognized by their larger tubercles and by the 

 stronger depression surrounding the petals. They may 

 further be distinguished by the less developed ambulacral 

 furrows and peristomal star, although the same may be 

 the case in certain varieties of L. depressum , which thereby 

 show a greater similiarity with L. multiforme. Moreover 

 in those specimens, where the anus is elliptical, the fact 

 that its longest diameter is parallel to the longitudinal axis 

 of the test and finally the circumstance, that the fossil does 

 not attain the dimensions of the recent species, may serve 

 to distinguish them from specimens of L. depressum. The 

 dimensions of the largest specimen are: 



length z= 29 mm. 



greatest width = 26 mm. 



ISTotes from the Leyden Museum, Vol. II. 



