176 THE FOSSIL ECHINOIDEA 



A second test from the same locality is somewhat larger ; but has been too much 

 crushed for measurement. 



Locality. In the Khirthar series of strata : — Baili, west of Tong. Survey-number 



G304 

 23 • 



Illustrations of the Species in Plate XXXI. 



Fig. 1. Abactinal view of the test : natural size. 



2. Actinal view of the test : natural size. 



3. Longitudinal profile of the test : natural size. 



4. Abactinal area, showing the ambulacral petals and apical disk ; magnified. 



5. The peristome and surrounding portions of the test : magnified. 



There is a very small specimen, measuring 10 millim. in length, from a locality 



five miles east-fifteen-north of Ghatana Trig station near Jhimpir (Survey-number -jQg-), 



which we refer with some hesitation to the same form as the above. This form accords 

 in shape, proportions, and general characters with that above described ; but is remark- 

 able for the immature state of the odd anterior ambulacrum. The example is obviously 

 too immature for accurate determination. 



12. EcHiNOLAMPAS, sp. Plate XXXVI, Figs. 22 & 23. 



There is a single specimen of a small Echinolampas in the collection, which is 

 certainly distinct from the other forms we have described ; but which is unfortunately so 

 much obscured by matrix that a complete description is impossible. 



The test is subdepressed, with a rotund marginal contour, the greatest breadth 

 being between the posterior part of the lateral interradia. The length is about 

 29 millim., and the estimated breadth 27 millim. The height is about 14 millim. ; and 

 the dorsal surface seen in longitudinal profile presents a remarkably regular convexity, 

 sloping uniformly anteriorly and posteriorly, and springing direct from the ambitus, 

 which is well, but rather abruptly, rounded on to the actinal surface. 



The apical disk is excentric in front ; it is comparatively large, and the central 

 portion, which is occupied by the madreporiform body, is slightly elevated. The 

 ambulacra are comparatively narrow, but conspicuously petaloid, the zones of a 

 petal converging considerably towards the outer extremity. The posterior petals are 

 rather longer than the anterior pair. The poriferous zones are unequal, the left 

 zone of the odd anterior ambulacrum and the anterior zone of the antero-lateral 

 petals, and thfe posterior zone of the postero-lateral petals being shorter than their 

 respective companions ; the inner series of pores are round and the outer pyriform, 

 with the pores of a pair rather wide apart, and united with a well-defined conju- 

 gating furrow. The divisional costse appear to be smooth and devoid of tubercles or 

 granules. The width of the poriferous zone is rather less than half the width of the 

 interporiferous area at its widest part. The other structures of the test are obscured. 



Bemarhs. This species is interesting from its occurrence in the white limestone in 

 company with great numbers of Hemiaster digonus ; and no other species of Echino- 

 lanvpas are associated with it. On these accounts we consider it desirable to record 



