H 



W 



0-42 



0-42 



0-40 



0-42 



FROM WEST PAKISTAN 27 



Dimensions (mm). 



L 

 Io. 4321 Carapace male (holotype) 076 



Io. 3115 Carapace female 0-73 



Comparison. Bradley a ? cornuelina (Bosquet) Keij (1957) is similar to B ? 

 voraginosa in lateral view but has three rather than two longitudinal ridges. Further, 

 it has a less well-developed anterior cardinal angle. Bradleya approximata (Bosquet) 

 Keij (1957) has a different posterior and larger posteroventral spines. 



Genus BUNTONIA Howe 1935 

 Type species. Buntonia shubutaensis Howe 1935. 



Buntonia devexa sp. nov. 



(Plate 13, figs. 1-5) 



Derivation of name. Latin devexus, sloping ; with reference to the tapering 

 lateral outline. 



Diagnosis. A species of Buntonia in which carapace is elongate, subrectangular 

 in lateral view ; surface ornamented with 9-1 1 longitudinal ribs in posterior three- 

 fifths of carapace. 



Holotype. Io. 4322, a female carapace (PI. 13, figs. 2, 4, 5). 



Paratype. Io. 3113. 



Material. 8 specimens from the locality and horizon below. 



Type locality. Rakhi Nala section. 



Type horizon. Gorge Beds, sample no. 3111. 



Description. Sexual dimorphism rather pronounced ; the males are longer and 

 less wide than the females. Carapace sub-triangular in lateral view, tapering 

 towards the posterior. Anterior margin broadly and obliquely rounded, posterior 

 narrowly rounded, dorsal and ventral margins almost straight, dorsal margin slopes 

 downwards towards posterior. Greatest length passes through the midpoint, 

 greatest height in the anterior third and greatest width in the posterior two-fifths. 

 Anterior cardinal angle rounded. Left valve slightly larger than the right valve. 

 Surface ornamentation consists of 9-1 1 longitudinal ridges, which are more or less 

 confined in the posterior three-fifths. Anterior marginal rim distinct. 



Dimensions (mm). 



L H w 



Io. 3113 Carapace male o-8o 0-39 0-24 



Io. 4322 Carapace female (holotype) 073 0-35 0-27 



Comparison. Buntonia virgulata Apostolescu (1961) has punctae between 

 longitudinal ridges and a less elongate carapace. Cythere cf. costellata (Roemer) 

 Latham (1938) is similar and may even be conspecific. However, her figure, which 



