BY W. N. BENSON, W. S. DUN, AND W. R. BROWNE. 343 



Schdlu'ieneUa crenistria, Thomas, The British Carboniferous Orthotetinae, Mem. 

 Geol. Surv. Gt. Brit., Pal. I., Pt. ii., 1910, p. 92. 



Tliis readily recognised form was found by Benson at the railway cutting four 

 miles east of Currabubula, and again in the south-east of Babbinboon. The largest 

 specimen found, if perfect, would have had a breadth of 70 mm. and length o'c 

 40 mm. 



According to De Koninck (30) this form is rather rare in the Lower Car- 

 boniferous but very abundant in the upper beds of the Carboniferous Limestone. 

 Modern British workers, however, have divided O. crenifstria into a number of 

 varieties of which the most important form is termed Schellwienella crenistria 

 and recognise the species sensu strieto extending from the base of the Car- 

 boniferous up to the zone Ca,* while varieties, e.g., var. senilis, extend up to the 

 zone D2. It has even been found in the Millstone Grit of the Welsh Border (31, 

 p. 251) (? a facies of D2) . It is apposite here to cite a remark of Davidson 

 (31, p. 290) apropos of Streptorhi/i/chns cnenistria var. senilis. — "Some palaeont- 

 ologists seem disposed to erect this important variety into a distinct species, and 

 it cannot be denied that in some localities, particularly in Au.stralia, it alone 

 occurs." 



Chonetes aspinosa Dun. 



Dun, Rec Geo! Surv. N.S.W., vii., 1902, p. 69, t. 19, f. 1-3, t. 20, f. 1-5. 



This species was proposed by Dun to receive forms previously classed as 

 Chonetes cf. comoides, Daviesiella cf. comoides, or Productus cf. giganteus. Pro- 

 bably should be here included the form referred to the last designation which was 

 obtained by Mr. Pittman from Somerton. Forms compared, but not identified with, 

 any one of the three above-mentioned species, are cited as occurring between the 

 zones Ci and Di in the Carboniferous rocks of Great Britain. 



Chonetes cf. habdbensis (Phillips). 



For Bibliography see De Koninck, Pal. Foss. N.S.W. Mem. Geol. Surv. N.S.W., 



Pal. No. 6, 1898. pp. 66-8. 



Two small specimens, not well preserved, which may be referred to this spe- 

 cies were obtained by Benson from the railway cutting four miles east of Curra- 

 bubula. The dimensions of these were length, 5 ram., breadth, 8 mm. 



This form occurs both in Devonian and Carboniferous beds of this State as 

 elsewhere, though De Koninck (op. cit.) urges that specific differences may be 

 found between the types belonging to the two Periods. This, however, does not 

 appear to be the view of modern British workers who record it as ranging from 

 the base of the Carboniferous System up to the zone C2. 



Productus hemisph.*ericus (Sowerby). (Plate xix., fig. 8.) 

 Jas. Sowerby, Min. Conch., 1822, t. 328; Productus giganteus var. hemisphaericus, 

 Davidson, Brit. Carb. Brach., 1858. p. 144, t. 40, f. 4-9. 

 Of this form there is only the cast of a pedicle valve available for study. 

 It agrees so closely with Davidson's diagnosis and figure that no individual de- 

 scription is necessary here. Its dimensions are: Length, 28 mm.; breadth, 35 

 mm.; length of hinge line, 30 mm. 



This form was obtained by Benson from the south-east of Babbinboon, and 

 is in the collection of the University of Sydney. It was also recorded by Dun as 



•For the explanation of this notation, see p. 368. 



