REPORT ON THE STOMATOPODA. 
97 
and there are few (five or six) marginal spines on the outer edge of its exopodite. In 
the older larvae the dactylus of the raptorial limb shows traces of six spines besides the 
marginal one. 
In the youngest Alimerichthus which has been observed (PL VIII. fig. 8) the 
flagellum of the second antenna is represented by a bud, as are also the appendages of 
the third thoracic somite, and the third, fourth, and fifth thoracic somites are crowded 
together so that the sum of their lengths is about equal to the length of each one of the 
three last thoracic somites, upon which there are no traces of appendages. There are five 
pairs of fully developed and functional abdominal appendages, and five distinct abdominal 
somites, the first four wider than the thorax, but the fifth very narrow and deeply con- 
stricted off from the telson, upon the anterior edge of which the sixth pair of abdominal 
appendages are represented by buds. The telson is wider than long, and nearly four 
times as wide as the abdomen. It has six pairs of marginal spines with numerous 
minute secondary spines between the submedians, ten or eleven on each side between the 
submedian and adjacent intermediate, and a single one internal to the base of the lateral. 
The margin of the telson, between the submedian and the intermediate, makes an angle 
of about 45° with the principal axis of the body, A comparison of this larva with the 
corresponding stage of Alima gracilis (PI. IV. fig. 5), or of Alima macroplithalma 
(PI. VIII. fig. 1), shows that there is every reason for believing that it is preceded 
by an earlier stage like the youngest observed stage of Alima gracilis (PI. IV. fig. 4), 
of Alima macrophtlialma (PI. VII. fig. 2), or Alima ( Squilla ) empusa (PI. I. fig. 4), 
and that at this time the third, fourth, and fifth thoracic somites are long and without 
appendages like the sixth, seventh, and eighth ; the fifth abdominal somite and its 
appendages absent or rudimentary, the sixth absent, and the telson spatulate, with the 
submedians wide apart, and the secondary dentations between the submedians and inter- 
mediates about as large as the primary spines. As we know that some, and probably 
all, of the Alima larvae hatch from the egg in this condition, and do not pass through a 
free Erichihoidina stage, this is undoubtedly true of the Alimerichthus also. 
In the next stage which has been observed (PI. IX. fig. 3) the appendages and 
somites are all present, the exopodites of the first five abdominal appendages carry at 
their bases the rudimentary buds which are to become the gills, the telson is shorter 
and wider than before, and the intermediate marginal spines have travelled backwards 
until the posterior margin of the telson is nearly transverse between them. The sixth 
abdominal appendages are still small, but in the next stage, the one shown in Claus’s 
fig. 30, they are nearly as long as the telson, with six or seven marginal spines on the 
outer edge of the exopodite and with the inner spine longer than the outer, with an 
obscure lobe on its outer margin near the base. The whole hind body is now wide and 
flat, and there are indications of five or six marginal spines on the inner edge of the 
dactylus of the raptorial claw. 
(ZOOL. CHALL. EXP. — PART XLV. 1886.) 
Yy 13 
