122 Dr. T. Wrif>:ht on Fossil Echinoderms 



'o 



form and development ; but the single interambulacrum is 

 diflferent, it forms a more convex eminence than the others 

 above, and is produced into a slight caudal appendage behind. 

 The apical disc is small and excentral, situated nearer the an- 

 terior border. The madreporiform body occupies the centre, 

 around which the four genital holes are pierced. The base is 

 concave ; the mouth is nearer the anterior border, is transversely 

 oblong, and surrounded by five lobes, formed by the termination 

 of the interambulacra ; the posterior single lobe is the largest ; 

 the anterior pair are next it in size, and the lobes of the postero- 

 lateral areas are the smallest and most contracted. Between 

 the five oral lobes, the poriferous terminations of the ambulacral 

 areas form petaloidal depressions, which are perforated with 

 numerous holes ; these run out and form lines which indicate 

 the basal boundaries of the areas. The anus is transversely 

 oval, x\yths of an inch in its long diameter, is more convex on 

 its anterior than its posterior border, and is situated close to the 

 margin; it is rather larger than the mouth-opening. The 

 tubercles are small, uniform in size, and closely set together on 

 the dorsal surface, and longer and more widely apart on the base. 



Affinities and differences. — The great convexity of the dorsal 

 surface, the greater elevation of the posterior than the anterior 

 half thereof, the inflated ridge-like eminence formed by the 

 single interambulacrum, and thewell-defined character of the pori- 

 ferous avenues, form a group of characters by which E. Kleinii 

 is distinguished from its congeners. It has many points of 

 resemblance in common with E. oralis; but the greater length 

 of the ambulacral areas in this species makes a marked distinc- 

 tion between them ; moreover, in E. Kleinii the base is concave, 

 whilst in E. oralis it is convex; the latter form is likewise 

 flatter and more oval, and its apical disc more exccntral than in 

 E. Kleinii. 



Stratiyraphical position. — Collected at Malta, from bed No. 2, 

 where it is very rare. It is found, according to Goldfuss, in the 

 Miocene beds at Biiude, Osnabruck, Astrapp, and Merminghiifen, 

 in Westphalia. 



History. — Admirably figured and well described by Goldfuss. 

 The only Maltese specimen we have seen of this species is that 

 collected by the Earl Ducie, which is in his lordship^s museum. 



Echinolampas Deshayesii, Desor, sp. PI. IV. fig. 3 a-d. 



Syn. Echinokimpas Hayesiana, Agassiz and Desor, Cat. raisonne, 

 Ann. So. Nat. tom. vii. p. 166. 



Test oval, depressed ; ambulacral areas narrow ; the poriferous 

 zones contracted, without apparent connecting transverse sulci ; 



