BY W. N. BENSON, W. fS. DUN, AND W. K. BROWNE. 347 



The last is a small form obtained by Benson from the railway-cutting, four 

 miles east of C'urrahubula. 



This form ranges from the base of the Carboniferous to the Upper Limestone 

 Series in Scotland (31), and is most abundant in the Upper Carboniferous Lime- 

 stone of Belgium, though extending to the lower portion (30). In England it 

 ranges from Ci to Di. It also is found in the Permo-Carboniferous beds of this 

 State. 



DiELASMA SACOULUM (Martin) var. amygdala (Dana). (Text-tig. 12.) 



Terebratula amygdala, Dana, Amer. Jour, of Science (4), ii., p. 152; also in 

 Report Wilke's U.S. Esplor. Exped., Geol., 1849, p. 682, t. 1, L 2a, b. 



This variety differs from D. hastata in its very elongated form. The figured 

 specimen, now in the collection of the University of Sydney, was obtained by Mrs. 

 Scott from the south-east of BabbLuboon, and has the following dimensions: — 

 Length, 27 mm., breadth, 17 mm., thickness, 12 mm. 



This form also has been obtained from the Burindi rocks at Somertoii, 

 represented by specimen 1511 in the collection of the Geological Survey. This 

 was tig-ured (Mem. Geol. Surv. N.S.W., iv., t. oS, f. 8) a.s D. hastata. At pre- 

 sent its Museum label is D. hastata amygdala (Dana). 



The form was first described from the Upper Marine Permo-Carboniferous 

 Beds which are probably Permian (4) . 



Spirifera bisulcata (Sowerby.) (Plate xxi., fig. 1.) 



J. Sowerby, Min. Conch., iii., 1820, p. 17, t. 23, f. 2, 3; Ddvidsou, Brit. Carb. 



Brach., 1850, p. 31, t. 4, f. 1 (?); t. 5, f. 1 ; t. 6, f. 1-19; t. 7, f. 4; 



L. G. de Koninck, Foss. Pal. N. Galles, 1877, (English Translation, 



1898, p. 192-3, t. 14, f. 5.) 

 This form is smaller than S. striata, and is characterised by the deep sulcus 

 on either side of the mesial fold. The form figured here closely resembles David- 

 son's figure {Op. cit., t. 6, f . 8) of Sowerby's type specimen. There are thirteen 

 ribs on either side of the sinus, in which are three obtusely rounded ribs . Length, 

 about 25 mm.; breadth 26 mm. Locality,— S . E . Babbinboon. Collected by 

 Mrs. Scott. This form was also obtained by Mr. Pittman, 5 miles S.E. of Somer- 

 ton. In the railway-cutting, four miles east of Currabubula, Benson has col- 

 lected small and rather more transverse specimens, with a greater number of ribs, 

 resembling Davidson's t. 6, f. 19. This form has the sulci on either side of 

 the mesial fold more strongly marked, and small ribs intercalated near the margin 

 separate the three low, broad ribs on this fold, and these are slightly sinuous. 

 Length, 15 mm.; breadth, 32 mm. De Koninck points out that this species is 

 very al)undant in the upper beds of the Carboniferous Limestone at Vise in Bel- 

 gium and in Great Britain, but occurs also in the Lower Limestone Series and 

 Calciferous Sandstones of Scotland (31) . In England and Ireland the range is 

 from the zone C2 to D2, and also extends into the Millstone Grit (31, p. 251) . 



Spirifera davidis Dun. 

 Rec. Geol. Surv. N.S.W., vii., 1902, p. 323, t. 60, 1. 1, a-f. 



This species was obtained by Cullen from the Parish of Moorowarra, south 

 of Somerton, and also near Carroll. (See specimens 4360, 4374 and 4390 of the 

 collection of the Geological Survey). Nothing need here be added to the descrip- 

 tion previously given. 



