484 J. W. Gregory — Australian Echinoidea. 



open below. The pore pairs of the anterior pair slightly unequal. 

 Those of the posterior pair markedly so. 



Mouth anterior : in the highest part of the actinal depression : 

 pentagonal : phyllodes very rudimentary. 



Anus triangular : infra-marginal. 



Dimensions. 



Length 43 mm. 



Width: at J of length from anterior end 36 ,, 



,, ,, posterior end 36 - 5 ,, 



Height 21 ,, 



Distance of apical disc from anterior end 17 ,, 



Length of petaloid portion of anterior ambulacrum 10 ,, 



Max. width of ,, „ ,, ,, 3 „ 



Length of petaloid portion of posterior f anterior poriferous area 17 ,, 



ambulacrum \ posterior area 12 ,, 



Max. width of ,, ,, ,, ambulacrum 3 - 5 ,, 



This species belongs to the group of Echinolampads of which 

 E. similis, Ag., may be taken as the type. It differs from this by 

 its greater proportional breadth, and the greater inequality of the 

 poriferous zones in each of the posterior petals. It can be easily 

 distinguished from other Australian species of this genus by its 

 depressed form and the marked inequality in the length of the 

 poriferous zones of the petaloid portions of the posterior ambulacra. 

 Its general form reminds one of Echinolampas dispar, Fritsch, 1 from 

 the Eocene of Borneo ; from this it differs in that the mouth is more 

 excentric in position, the anus is triangular (instead of round as in 

 the Malaysian species), and in the latter the posterior part of the 

 test is much wider than the anterior. 



Fam. Ananchytid.e:. 



Genus Cardiaster, Forbes, 1852. 



Cardiaster tertiarius, sp. nov. PI. XIV. Figs. 2 & 3. B.M. E 3382. 



Outline seen from above cordate : the test tapering gently 

 posteriorly ; the anterior end is broad, well rounded, and marked 

 by the deep anterior groove. In elevation it is seen to be sloping 

 steeply in front and very high behind ; the posterior interradius is 

 elevated into a slight keel. Vertex at a quarter of the length of 

 the test from the anterior end. Posterior margin truncate and 

 vertical, with the anus high upon this area. In this position the 

 actinal surface appears straight. 



Apical system central ; elongate ; only the right half is known. 



Ambulacra flush : the pores of the posterior poriferous zones of 

 each of the paired ambulacra larger than the anterior. Pores of 

 unpaired anterior ambulacrum minute. 



Tubercles crenulate and perforate. 



Dimensions. 



Length 42 mm. 



"Width at | length from anterior end of test 21 ,, 



» „ posterior ,, ... 18 ,, 



Height 25 „ 



1 K. von Fritsch, "Die Echiniden der ISTummuliten-Bildungen vou Borneo," 

 Palseontographica, Supp. III. 1. 1, Hft. 2, 1877, p. 89, pi. xiii. figs. 2 and 3. 



