NAMES GIVEN WITH A PURPOSE 287 
tylus chiragra (Fabricius). The species appears to have 
a vast range, and its colour is said to be exceedingly 
variable. 
Coronida, Brooks, 1886, has the carapace flat and 
nearly rectangular. The rostrum ends in a small median 
spine; the scale of the second antenne is very small; the 
terminal joint of the second maxillipeds is dilated at the 
base, and armed with spines on the inner margin. The 
pleon is depressed; its hind segments and the telson 
are thickly set with small spines. The uropods are very 
small. The name of the genus is compounded from the 
names of the rejected genera Coronis and Chlorida (or 
Chloridella), to indicate Professor Brooks's view that like 
them it contains somewhat primitive species. ‘These are 
Coronida Bradyi (A. Milne-Edwards) and Coronida trachi- 
rus (Miers), both of which were originally assigned to 
Gonodactylus. The professor seems inclined to suspect 
that the sixth pleon-segment may prove to be fused with 
the telson, but the type-specimens of Miers’s species in the 
British Museum show that at least in Coronida trachurus 
the telson is quite distinct from the preceding segment 
and freely movable upon it. 
Protosquilla, Brooks, 1886, has the rostrum furnished 
with long acute median and anterolateral spines; the eyes 
and the scale of the second antennz small; the terminal 
joint of the second maxillipeds dilated at the base, with- 
out marginal spines; the pleon convex, its sixth segment 
more or less completely fused with the telson ; the uropods 
small. Professor Brooks considers the name of this genus 
‘the more appropriate inasmuch as all the other Stomato- 
noda present evidences of divergent descent from a 
common stem form, which, like the living representatives 
of the genus Protosyuilla, was characterised by the small 
size of its eyes, antennary scales, and uropods.’ Seven 
species are included in the genus, among which Proto- 
squilla elongata, Brooks, with a carinate and bilobed but 
otherwise simply constructed telson, presents a rather 
striking contrast to Protosquilla Guerinii (White), in 
which the dorsal surface of the telson carries twenty-two 
