SYNOPSIS OF THE PRINCIPAL GROUPS. 103 
Catalogue of the Echinodermata of New Zealand.—Hutton, Geologi- 
cal Survey Department, Wellington, 1872. 
Corrections and Additons to ditto.—Hutton, Trans. N.Z. Inst., IX., 
p. 362, and XI., p. 305. 
Catalogue of the Tertiary Mollusca and Echinodermata of New 
Zealand.—Hutton, Geol. Survey Department, Wellington, 1873. 
ARTHROPODA.—Body composed of segments, bearing 
pairs of hollow, jointed appendages. Oral apparatus 
formed by modified appendages. Hzemal system dorsal. 
Nervous system a cephalic ganglion connected with a 
double row of ganglia on the ventral surface of the 
body, which is traversed anteriorly by the cesophagus. 
Never furnished with cilia at any period of their 
existence. 
CrustTAckA. Respiration by branchie ; legs more than 
eight; two pairs of antenneze. 
There are five sub-classes: 
Cirripedia. Body furnished with a mantle, 
and enclosed in a many-valved carapace ; ab- 
domen rudimentary ; feet in the form of cirri. 
Epizoa. Body elongate, sub-articulate; the 
antenne and limbs terminated either by 
suckers, hooks, or bristles; mouth suctorial ; 
no respiratory organs; parasitic. 
Entomostraca. Body furnished with a carapace 
consisting of one or two valves ; limbs jointed, 
setiferous ; branchize attached to the limbs or 
to the oral appendages. 
Edriophthalma. Eyes sessile; no carapace ; 
head, thorax, and abdomen distinct, the two 
latter segmented ; branchize more or less con- 
nected with the legs. 
