35 



crifice prolonged in a long shaft, base bilobed; cornuti a 

 large scobinate patch on the vesica. 

 Ostium thickened at either side. 



sabulicola, WUm. 



Valvula almost pointed; sacculus rounded; costa produced 

 upward, spined at and below the tip; transtilla a mere 

 projection. Socii short. .Edoeagus orifice prolonged in a 

 strong, curled hook, base hardly bilobed; cornuti a large 

 scobinate patch on the vesica. 

 Ostium very delicate. 



subroseana, Haw. 1—1 



F. G. Whittle,. J. W. Cordcr. 



Valvula slopes upward, almost pointed; sacculus not 

 rounded; costa produced upward, spined at the truncated 

 tip; transtilla centrally produced, armed with a few teeth. 

 Socii very short. iEdoeagus orifice prolonged in a long, 

 slender shaft; base rounded; cornuti a roughly scobinate 

 patch on the vesica. 



Ostium weak; ductus bursic strongly thickened. 



rupicola, Curt. 



■I. Gardner, /■'. (<■ Whittle, .1. /-:. Atmore. 

 This species provides the key to the separated costa of the 

 three preceding species. In this it returns to its normal 

 position, fused to the valvula and Spined at the tip, thus 

 forming an emargination between the valva and sacculus; 

 sacculus a broad plate; transtilla centrally produced, armed 

 with many spines at the tip. Socii fairly short, drooping. 

 TEdceagus orifice with short shaft; base rounded; cornuti a 

 scobinate patch on the vesica. 



Ostium more developed than preceding species. 



