REPORT ON THE STOMATOPODA. 
9 
more typical species of the genus Squilla, such as Squilla nepa, have broad triangular eyes, 
an elongated carinated carapace with acute spines at its antero-lateral angles, longitudinal 
carinse on all the abdominal somites, the appendages of the exposed thoracic legs filiform, 
and the telson longer than wide, with well-developed marginal spines, of which only the 
submedians are on the posterior border, and the others lateral. In Squilla lata (PL III. 
figs. 1, 2, 3) the eyes are narrow and only slightly enlarged at their tips, the appendages of 
the exposed thoracic limbs are flat, and the submedian carinse are absent or obsolete on 
the first five abdominal and all the thoracic somites. In Squilla fasciata (PI. III. 
figs. 4, 5) the e}ms are cylindrical, not at all dilated at the tips, the appendages of the 
exposed thoracic limbs are flat and strap-shaped, and the submedian dorsal carinse are 
completely absent on the first five abdominal somites ; while in Squilla chlorida 
(PI. II. figs. 1-5), which is not usually regarded as a Squilla, but is placed in a distinct 
genus Chloridella, the eyes are constricted at the tips, the appendages of the exposed 
thoracic appendages broad and flat, and the submedian carinse absent from all the 
exposed somites except the sixth abdominal; and in Squilla ( Chloridella ) microphthalma 
the eyes and appendages are like those of Squilla chlorida, but the dorsal surfaces of 
the exposed somites are smooth, and their lateral edges but faintly carinated, and the 
telson is wider than long, and the uropods small. In all these species the antero-lateral 
angles of the carapace are acute, but in Squilla ( Chloridella , ) rotundicauda we have, in 
addition to the wide telson the small uropods and eyes and antennary scales of Squilla 
microphthalma, a loosely articulated hind body, a carapace which is rounded in front as 
well as behind, and the posterior margin of the telson rounded. 
The series is so complete that it is quite impossible to draw any line to separate the 
genus Squilla from the genus Chloridella, and all the species must therefore be 
associated in a single genus Squilla. It is easy to find an answer to the question, which 
term in the series of species of Squilla is most primitive, for while the large multi- 
carinated Squillse are so different from the Lysiosquillae that there can be no question as 
to their distinctness, it is difficult to discover any characteristics which shall separate 
Squilla microphthalma from the latter genus ; but we find that this species does not 
resemble all species of Lysiosquilla to an equal degree, for the genus includes species, 
like Lysiosquilla ( Coronis ) excavatrix (PL X. figs. 8-16), which have, like Squilla microph- 
thalma, small eyes and uropods, and flat wide appendages to the exposed thoracic 
limbs ; as well as species which, like Lysiosquilla maculata, have these appendages 
linear and the eyes broad and triangular. We may therefore state with confidence 
that Lysiosquilla maculata and Squilla nepa are more divergent than Lysiosquilla 
excavatrix and Squilla microphthalma, and that the two genera are divergent branches 
from a common type, from which both genera have inherited the flat hind body and the 
many-spined raptorial claw ; and that this ancestral form had small eyes, antennary 
scales and uropods, and a transverse telson. 
(ZOOL. CHALL. EXP. — PART XLV. 1886.) ' Yy 2 
