CHARACTERISTIC SPINES 28) 
Family Squillide. 
As this is now the only family, it has the characters of 
the sub-order. The family Erichthidee, which was formerly 
its companion, has been shown to consist entirely of larval 
forms. Inthe Squillidee Brooks accepts ‘ seven genera, Pro- 
tosquilla, Gonodactylus, Pseudosquilla, Coronida, Lysiosquilla 
(including Coronis), and Squilla (including Chloridella), 
As only six genera are named, it is doubtful whether seven 
is a misprint, or intended tacitly to include Leptosquilla, 
Miers, which had been previously spoken of as very slightly 
known. Professor Brooks lays great stress on the marginal 
spines of the telson, of which there are usually six, arranged 
in three pairs. These he designates as the primary mar- 
ginal spines, and distinguishes the two nearest the middle 
line as the submedians, the two nearest the anterior edge, 
which are usually the farthest from the middle line, as the 
laterals, and the one between the lateral and the submedian 
on each side as the intermediate. ‘ Between these six 
primary marginal spines there are others which are equally 
large and prominent in the young larve, but minute or 
absent in the adults;’ these he calls the secondary mar- 
ginal spines. ‘The characters of the great second maxilli- 
peds, spoken of as the raptorial claws, and the connection 
of the sixth segment of the pleon with the telson, are also 
of great importance in distinguishing the genera. Another 
structure, which ‘ often presents characteristics of specific 
value, and differs conspicuously in the different genera,’ is 
that found upon the inner branch of the first pleopods in 
the male, ‘a complicated grasping organ which probably 
serves for seizing the female, like the grasping forceps of 
many of the lower Crustacea and some few of the Mala- 
costraca.’ 
Squilla, Fabricius, 1793, agrees with all the other 
genera, except Protosquilla (and perhaps Coronida), in 
having the sixth pleon-segment separated from the telson 
by a movable joint. The terminal joint of the second 
maxillipeds is without a basal enlargement, but with a 
series of spines, usually not more than six in number, on 
