194 MESSRS. ADAMS AND ANGAS ON NEW CHITONID#. [May 10, 
This species is very interesting from presenting us with another 
example of a peculiar Australian form. It differs from Z. volvox and 
L. cimolia of Reeve in the valves being much broader and less raised 
at the hinder parts, and in having the scales of the mantle smaller. 
Genus Micropuax, nob. 
Testa elongata. Valve partibus externis parvis, cordiformes, dis- 
juncte ; lamine insertionis magne. Limbus nudus. 
In this genus the exposed parts of the valves are very small, and 
are completely disunited, the distance between them in Microplax 
grayi being nearly equal to the length of the valves. 
7. MicrorLax GRAYI, nob. 
M. testa elongata, convexa, fusca; partibus externis valvarum 
minutis, late cordiformibus, carinatis, valde granulatis, inter- 
stitiis longitudinem valvarum viz equantibus ; areis lateralibus 
costa distinctis. Limbus mediocris, corneus, levis. 
Long. 13, lat. 5 mill. 
Hab. Sydney Harbour, under stones at low water (Coll. Angas.). 
8. HANLEYA VARIABILIS, nob. 
H. testa oblonga, albida, atro-fusco variegata ; valvis latis, cari- 
natis; areis dorsalibus longitudinaliter dense costatis, costis 
confertim pustulosis; areis lateralibus vix elevatis, transverse 
et undulatim costatis, costis confertim pustulosis. Limbus ad 
marginem spiculis brevibus, albis, corneis instructus, fasciculis 
spiculorum pallidorum. 
Long. 16, lat. 10 mill. 
Hab. York’s Peninsula (Coll. Angas.). 
9. ACANTHOCHITES CARINATUS, nob. 
A. testa elongata; valvis mediocribus, valde carinatis, postice 
mucronatis, albidis, rufo-fusco maculatis, ereberrime pustulosis, 
medio atro-fuscis, levibus ; areis lateralibus indistinctis. Lim- 
bus spiculis minutis albis obsitus, fasciculis spiculorum pal- 
lidorum. 
Long. 30, lat. 16 mill. 
Hab. Sydney (Coll. Angas.). 
10, ACANTHOCHITES COSTATUS, nob. 
A. testa elongata; valvis mediocribus carinatis, angulatim cor- 
datis, granulatis, pallido-fuscis ; areis lateralibus ab areis dor- 
salibus costis prominentibus divisis ; areis dorsalibus medio 
levibus, albidis. Limbus spiculis brevibus, albis, fugaceis ob- 
situs, fasciculis spiculorum alborum longiorum instructus. 
Long. 18, lat. 7 mill. 
Hab. Sydney (Coll. Angas.). 
