152 A. H. Foord — Western Australian Fossils. 



Prodtjctus subquadratus, Morris. Plate VII. Fig. 5. 



1845. Produetus subquadratus, Morris, in Strzelecki's Physical Description of New 



South Wales and Van Diemen's Land, p. 284. 

 ? 1847. Produetus subquadratus, de Koninck, Mon. du Genre Produetus, p. 203, 



Atlas, pi. xiv. figs. 1, a-d. 

 1878. Produetus subquadratus, Etheridge, jun., Cat. Australian Foss. p. 53. 

 1880. Produetus subquadratus, Etheridge, jun,, Proc. Roy. Phys. Soc. Edinburgh, 



vol. v. p. 283. 



Several tolerably well-preserved specimens are referred to this 

 species mainly on account of the well-marked mesial furrow which 

 distinguishes them, and is one of the chief characters in subquadratus. 



Mr. E. Etheridge, jun. (Proc. Eoy. Pbys. Soc. Edinb. vol. v. 

 1880, p. 283), refers to de Koninck's opinion that the present species 

 is only a form of P. bracliythcerus, G. Sow., 1 but he does not say 

 anything tending to confirm de Koninck's view. The specimen 

 forming part of the Strzelecki Collection in the British Museum, and 

 figured by Morris in Strzelecki's work on " New South Wales " 

 (pi. xiv. fig. 4c, not figs. 4a, 4&), 2 assuredly cannot belong to the 

 same species as the form named by Morris P. subquadratus, the type 

 of which I have now before me. The ventral valve of the latter is 

 extremely gibbous, and is divided into two prominent lobes by a 

 very distinct mesial furrow, a character well displayed in Mr. H. P. 

 Woodward's specimens. No such feature is to be found in P. bracliy- 

 ihcerus, nor has it apparently the numerous irregularly-disposed, 

 conspicuous spine-bases with which the surface of P. subquadratus 

 is beset. It would seem not improbable that the species doubtfully 

 referred by Mr. Etheridge to P. subquadratus is, after all, not that 

 one, because no mention is made of any mesial furrow in the 

 description, which is so marked a character in Morris's species, and 

 one therefore which could not possibly have been overlooked. 



Locality. — Irwin Eiver, Victoria District. 



Produotus undatus, Defrance. Plate VII. Fig. 6. 



1826. Produetus undatus, Defrance, Diet, des Sci. Nat. vol. xliii. p. 354. 



1843. Produetus undatus, de Koninck, Descrip. des Anim. Foss. du Terr. Carb. de 



Belgique, p. 156, pi. xii. figs. 2, a — c. 

 1845. Produetus undatus, de Verneuil, Geol. de la Russie d'Europe, et les Montagnes 



de l'Oural, vol. ii. pt. iii. Paleont. p. 261, pi. xv. fig. 15. 

 1847. Produetus undatus, de Koninck, Mon. du Genre Produetus, p. 156, Atlas, 



pi. v. figs. 3, a — c. 



1860. Produetus undatus, Trautschold, Nouv. Mem. Soc. Imp. des Nat. de Moscou, 



torn. xiii. p. 329, Taf. xxxii. fig. 2. 



1861. Produetus undatus, Davidson, Brit. Carb. Brach. vol. ii. pt. v. p. 161, 



pi. xxxiv. figs. 7 — 13. 



1877. Produetus undatus, de Koninck, Recherches sur les Fossiles Paleozoiques de 



la Nouvelles-Galles du Sud (Australie), pt. iii. p. 190, pi. ix. fig. 4. 



1878. Produetus undatus, Etheridge, jun., Cat. Australian Fossils, p. 53. 



This well-marked and widely-distributed species is represented 



1 In Darwin's Geological Observations on Coral Reefs, etc. pt. ii. 1851, Appendix, 

 p. 158. 



2 Dr. H. Woodward, F.R.S., and Mr. Etheridge, jun., proved that these figures 

 represent " a distinct and separate species," from fig. Ac, which is the true P. brachy- 

 thcerus (Proc. Roy. Phys. Soc. Edinburgh, vol. v. 1880, pp. 286, 287). 



