158 



general resemblance, W. snjjlata is at once known by its 

 incurved, minutely perforated beak. 



Locality and Horizon. — Bare in the yellow Polyzoal calcif erous 

 sands, forming the base of the sea cliffs, south side of AVillunga 

 JettyyAldiriga Bay; and rough shelly limestones at Surveyor's 

 Point and Stansbury, Yorke's Peninsula. Many examples. 



Terebratulina Scoulari, »pec. nov. Plate viii., figs. 3a— 3d. 



Shell pentagonal, about half as long again as wide, broadest 

 about the middle, tapering gradually towards the truncated 

 front ; sides and front slightly curved. Peduncular valve 

 uniformly convex, with a slight median depression in the 

 anterior half of the valve. Brachial valve moderately convex. 

 Surface ornamented with very numerous radiating rounded 

 ribs, which are repeatedly bifurcated ; the interspaces rather 

 narrower than the breadth of the ribs ; the entire surface 

 crossed by close-set concentric lines of growth ; the ribs about 

 the margins of the umbonal regions with imbricating scales. 



Hinge line narrow, arched ; beak moderate ; foramen, in the 

 adult, complete, circular, moderate, laterally margined by 

 small deltidial plates. 



Loop that of Terebratulina. 



Dimensions. — Length, 1/2 inch ; breadth, '75 ; thickness, '5. 



Observations. — T Scoulari belongs to the group typified by 

 T. caput-serjpentis, from which it differs in being more depressed 

 and attenuated towards the front, and in having the ribs and 

 concentric lines more numerous and finer; the form of the loop 

 is also different. In shape it closely agrees with T. Jctpohica, 

 as also to the recent Australian species T cancellata. From 

 the latter it differs in its more pentagonal outline, less inflated 

 valves, and coarser ribbing ; characters which are very pro- 

 nounced in the young. The annulus of the loop of T. Scoulari 

 is rather subcircular ; it is smaller and more contracted than 

 that of either of the above. 



The specific name is in compliment to Mr. Gavin Scoular, 

 who has so ably worked out the geology of Munno Para. 



Locality and Habitat. — Bare in the Upper Murravian, near 

 Morgan, and at Muddy Creek, Victoria {Tate). Common in 

 the Middle Murravian white ealeiferous sand rock. Not un- 

 common in the glauconitic limestones of Aldinga Bay {Tate). 

 Bare in the Muloowurtie clays, Torke's Peninsula {Temper). 



Terebratulina Davidsoni, Etheridge. PI. xi., figs. 6a— 6d. 



fief.—T. (?) Davidsoni, Annals and Mag. of Nat. Hist., 1876 r 

 t. 1, f. 1, p. 16. 



" Shell small, oval, flattened, tapering towards the beak, 

 rounded towards the front ; lateral margins in one plane, noi 



