114 PROF. r. J. BELL ON A NEW SPECIES OF 



Fig. 4. A compound plate close to the radial plate, from within. Magnified- 

 a. A similar plate, lower down, seen on the outside. Magnified. 



5. Echinothrix Desori, Agass., sp. A compound plate, four or five from the 



peristome ; x' is the line of the auricule. Magnified. 



6. The tenth compound plate from the peristome. Magnified, a. The 



same, from within. 



7. A part of ambulacrum No. 1, seen from within. There are four com- 



pound plates and a part of a fifth. Magnified. 



8. Some ambulacral plates near the peristome. Magnified. 



9. Astropyga radiata, Gray. A compound plate (Plate C. of fig. 10) made 



up of two triplets, after benzole. Magnified . 



10. Part of an ambulacrum, plates A, B, C, seen from within, showmg the 



arrangement of the triplets and the circular depressions which cor- 

 respond with the bases of the tubercles on the outside of the test. 

 Magnified. 



11. Micwpyga tuherculata, Agass. Three compound triplet plates of an 



ambulacrum above the ambitus. External view. Magnified. 

 All the figures are slightly diagrammatic. 



Description of a new Species of Miuyad {Minyas torpedo) from 

 North-west Australia. By Professor T. Jeppket Bell, 

 M.A., Sec. E.M.S. (Communicated by Dr. Gtjnther, F.E.S., 

 F.L.S.) 



[Eead 16th April, 1885.] 



The Trustees of the British Museum have lately acquired, by 

 purchase from Capt. Beckett, who has been sailing among the 

 islands which lie to the north-west of Australia, an interesting 

 example of this rare and little-known group. So little is known 





Upper surface of Minyas toiyedo, n. sp. X 2. 



with regard to the Minyadidse — the ' Challenger ' even collecting 

 but few specimens — that a short communication, though based 

 on but a single specimen, may be of interest to the Society. 



