102 THE VOYAGE OF H.M.S. CHALLENGER. 



they all died in moulting. The newly hatched young are swept out to sea by the tide, 

 and are widely distributed, and the older larvae are seldom found at Beaufort, but I have 

 procured a few specimens which serve to connect the youngest stage with a larva 

 nearly an inch long, which changed in the house into a young Lysiosquilla excavatrix, 

 so that there is little doubt that all the larvse of this type found there belong to this 

 species. 



The youngest larva which is figured is very similar to Claus's Erichthus 

 tnultispinosus from the Indian Ocean, although it is much younger, nor do they belong 

 to the same species, for Claus's specimen has eight or nine, and ours only three, secondary 

 spines between the intermediate and the submedian marginal spines of the telson, 

 altholigh in other particulars there is the closest resemblance between the two. 



It has four distinct well-developed abdominal somites with appendages, while the 

 short fifth abdominal somite is not yet separated from the telson. The flagellum 

 of the second antenna and the appendages of the last six thoracic somites are 

 absent, although the somites are present and equal in length, with the exception of the 

 eighth, which is longer than the others. The rostrum is about as long as the carapace, 

 and it has two or three small spines on its lower surface. The carapace covers 

 aU the thoracic, but not the abdominal somites, and its general outline, in dorsal 

 or ventral view, is nearly square, but its length slightly exceeds its greatest width, 

 and its width between the bases of the antero-lateral spines is less than between 

 the bases of the postero-laterals. In profile view (fig. 2) the lateral edges are 

 1ieut downwards below the level of the ventral surface of the thorax, and the chamber 

 which is thus formed is deepest at its posterior edge, so that the mid-dorsal outline and 

 the lateral edge are wide apart posteriorly, and approach each other in an acute angle at 

 the base of the rostrum. On the middle line of the posterior edge there is a slender 

 spine a little shorter than the rostrum, and about equal in length to the curved, 

 divergent postero-laterals, each of which carries a secondary ventral spine near its base, 

 dorsal to which, on the posterior edge of the carapace, there is a small secondary spine on 

 each side, as well as one on the lateral edge posterior to the base of each of the long, 

 divergent and widely separated antero-laterals, and on the lateral edge about halfway 

 between the antero- and postero-laterals there are two secondary spines. The telson is 

 considerably longer than wide, with its posterior edge nearly transverse, its anterior edge 

 narrow, and with six marginal spines on each side, the first, which is longer than the 

 next five, becoming the lateral marginal spine of the adult, is separated from the second 

 or intermediate by a wider space than those between the others. The eye-stalks are about 

 as long as the eyes, which are narrow with globular tips. The raptorial claw is flat and 

 oval, and there is a large prominent spine close to the proximal end of the carpus. 



The next larva which is shown as seen from the left and below (fig. 3) is con- 

 siderably older and larger, and the marginal spines of the rostrum and carapace have 



