50 
CATALOGUE OF ECHINIDA. 
Eupatagus Yalenciennesii, Agassiz & Desor , Ann. Sci. Nat. 
viii. 9, vi. t. 16, f. 13. 
Hab. Australia. Verreaux. 
Var. 1. Dorsal tubercles rather more numerous. 
Hab. Yan Diemen’s Land. 
a. b, c, d. With and without spines. Yan Diemen’s Land. 
Presented by It. Gunn, Esq. 
7. Plagionotus. 
Shell thin, depressed, elliptical ; summit excentric, anterior ; 
lateral ambulacra narrow, linear, rather sunken, the front pair 
rather transverse, elongate, the hinder pair rather longitudinal, 
anterior odd one on the crown of the shell ; back with large 
mammillonated tubercles placed in cross series, bearing long 
spines, and circumscribed by the slightly sinuated peripetalous 
fasciole ; anal fasciole very near the vent ; mouth anterior ; 
vent large, in the middle of the hinder edge ; ovarial pores 
four ; the hinder larger and far apart, with the madreporiform 
plate between them ; ocellar pores placed in front, and alter- 
nating with the ovarial pores ; the plastron linear, elongate ; 
subanal disk cordate, with a central groove, and series of pores 
on each side in the grooves from the centre. 
Brissus, § 1, Plagionotus, Agassiz & Desor , Ann. Sci. Nat. viii. 
1847, 13. 
Brissus, sp., Van Phelsum , 39. 
Spatangus, sp., Lamk. 
1. Plagionotus pectoralis. 
Dorsal tubercles numerous, in six or more rows. 
Echinospatangus, Seba, Mus. iii. t. 14, f. 5, 6. 
Brissus mcfgnus, Van Phelsum , 39, 48. 
Brissus pectoralis, Agassiz , Prod. 184. 
Spatangus pectoralis, Lamk. Hist. iii. 333 ; E. M. 1. 159, f. 2, 3 ; 
Deslong. E. M. ii. 686 ; Desmoul. Echin. 380. 
Echinus spatangus, var., Gmelin , S. N. 3200. 
Hab. Bahia. Mus. Paris. 
b. Moderate sized, part covered with spines ; dorsal tuber- 
cles rather more numerous. 
c. Large, without spines ; dorsal tubercles more numerous, 
in six rows, on the hinder half of the lateral interam- 
bulacral area ; the hinder part of the fascioles on right 
side not angularly bent up as on the other side. 
