R. ETHERIDGE, JITN., ON AUSTRALIAN TERTIARY ECHINODERMS. 447 



Wooclsii were obtained from Tertiary beds on the east shore of 

 Port-Phillip Bay, near the small township of Mordialloc. The de- 

 posit in question was mapped by Mr. A. B,. C. Selwyn as of Pliocene 

 age, and extends from the environs of Melbourne southwards along 

 the bay to Frankston, enclosing within its boundaries the great 

 Carrum Swamp. The section at the exact point where I obtained the 

 specimens, when in company with my friend and former colleague, 

 Mr. C. D'O. H. Aplin, is as follows, from above downwards : — 



a. Bed of sandy loam, containing fragments of marine shells, at present living 



in the bay, continuous along the coast for some miles. 



b. Thin bed of ironstone pebbles, well marked. 



c. Bed of ferruginous sand, with interbedded ironstone bands, intersected by 



vertical " pipes," containing white sand and an aluminous ( ?) material. 



d. Yellow sandstone, with a few ironstone bands, containing Ostrea, My till, 



Hemipatagus Woodsii, and fragments of other shells. 



e. A very thin band formed of the comminuted fragments of shells. 



/. Yellow sandstone, containing pieces of impure limestone, with a few fossils, 



H. Woodsii, &c. 

 g. Bed of concretionary ironstone, forming the beach at high- water mark ; 



the place of this is here and there taken by a band containing large 



shells in a tolerably good state of preservation. 



Many years ago this portion of the colony to the south of Mel- 

 bourne was examined by Mr. W. Blandowski, who gave in his 

 report* a section of the beds at a point some distance to the south 

 of Mordialloc, between Schnapper Point and Balcombe's Creek, 

 where beds of a similar nature to those now treated of again occur. 

 His section naturally differs a little from the one here given. 



Genus Psammechinus, Agassiz. 

 Psammechlnus Woodsi, Laube. Plate XXI. fig. 10. 



P. Woodsi, Laube, Sitz. d. k. Akad. Wissenschaften, Wien, 1869, 

 Band lix. Abth. 1, p. 185, fig. 1. 



When he described this elegant little form, Dr. Laube does not 

 appear to have possessed a specimen with a well-preserved apical 

 disk. Pig. 10 is the outline of a specimen in the Blanford collection, 

 showing the apical region. The genital plates are roughly trian- 

 gular, with moderately large pores. The madreporiform body on 

 the right antero-lateral genital plate is well marked and prominent. 

 The perforations of the ocular plates are not visible ; and the small 

 plates covering the central aperture have disappeared. 



Loc. — Banks of the Murray river ; Blanford Collection, M. P. G. t 

 one specimen. 



Genus Micraster, Agassiz. 

 Micraster brevistella, Laube. Figs. 11 and 12, p. 448. 



M. brevistella, Laube, I. c. p. 192, fig. 7. 



A well-preserved specimen of this species is also in the collection, 

 and clearly exhibits the ambulacral characters. Both the anterior 



* "Keport to the Hon. Surveyor-General, on an Excursion to Frankston, 

 Balcombe's Creek, Mount Martha, Port Phillip Heads, and Cape Shank," 

 Trans. Phil. Inst. Victoria, i. p. 27. 



Q. J. G. S. No. 123. 2 h 



