186 PEOF. p. M. DUlSrCAls's EEVISION OP THE 



Fossil. Australian Tertiaries (Studeria (Catopy^us) elegans, 

 LaulDe, sp.)' 



Recent. Australian seas, south of Cape of Grood Hope, East 

 Indian Archipelago*. 



The Eocene representative of the Cretaceous Catopygi found 

 in W. Sind is a very striking form, leading from the Cretaceous 

 type to the recent forms classified under Studeria. The shape 

 of the test, the small dorsal ambulacra! rosette, the single series 

 of estrapetalous pores, the character of the floscelle, and the 

 low position of the pcriproct distinguish the species, and require 

 the definition of a new and closely allied genus. 



Genus Neocatoptgus, Duncan 8f Sladen, 1882, Fal. Ind. ser. xiv., 

 Mss. EcJi. W. Sind, p. 76. 



Test of moderate size, tumid and high, subrotund marginally, 

 greatest height excentric posteriorly. Abactinal area convex; 

 sides tumid, high ; actinal surface convex, posterior extremity 

 subrostrate and prominent. 



Apical system excentric slightly in front, small, compact; four 

 basals, all perforated for the genital ducts ; madreporite large in 

 the right anterior basal, and extending so as to separate the other 

 basals. 



Ambulacra petaloid ; petals short and subequal, open at the 

 extremity ; pores unequal ; extrapetalous pores single. Eloscelle 

 well developed ; phyllodes with an inner series of supplemental 

 pores. 



Peristome small, pentagonal, excentric in front, bourrelets 

 forming an ornamented wall-like rim. Periproct small, subcir- 

 cular or oval, low, supramarginal, placed at the extremity of the 

 posterior rostration. Subanal area tumid and rostrated, faintly 

 grooved. 



Tubercles small, perforate and crenulate, sunken in deep scro- 

 bicules. Actinal ornamentation the coarsest. 



Fossil. Eocene: Asia (W. Sind). 



* The genus Oolopygus, d'Orbigny, 1856, only differs from Catofygus, in the 

 unimportant matter of the pores of the pairs not having a groove between them. 

 This defect has no physiological bearing ; and indeed it is doubtful whether all 

 the pairs of CA'ery specimen of a species of Catapygus are united by a groove. 

 Oolopygus of the Upper Chalk is a synonym of Catopygiis. 



