REPORT ON THE STOMATOPODA. 



89 



mated to each other at each successive moult, are now separated by a space equal to only 

 T^^ or less than ^ of the total length, while in stage 1 the distance between them is 

 y^^5 of the total length. As shown in PI. VIII. fig. 6, there are fourteen short acute 

 spines between the submedians, with still smaller spines between them, and there are 

 fifteen small acute dentations between each submcdian and the intermediate of the same 

 side, which is about equal in length to the submedian. 



The uropod of a specimen of the same size, which was captured at the surface by the 

 Challenger expedition, between Api and Cape York, is shown in ventral view in PI. VIII. 

 fig. 4. The exopodite is now divided into a paddle and a second joint, and the latter 

 has five spines on its outer margin. The ventral prolongation from the basal joint ends in 

 a short outer spine and a much longer inner one, which has a rounded lobe on its outer 

 margin, near the base. 



From the table of measurements given above the following measurements may 

 be selected as showing the character of the changes through which the larva passes 

 during its growth. They are all in thousandths of the total length from the tip of the 

 rostrum. 



While Alima gracilis differs from ordinary Alimie in many respects, especially the 

 great elongation of the body, the shortness of the carapace, and the elongation of the 

 telson, Claus has figured a series of Alimas which shows that the shorter and wider 

 species are connected with the elongated ones by so many intermediate forms that tliere 

 can be no doubt that the adults which they represent are all closely related. The 

 Challeno-er collection also contains jrrcat numbers of these intermediate forms, and I 



DO ' 



give in PL VII. fig. 7 and PI. VIII. fig. 7 figures of the telson and the raptorial claw 

 of one of them, which resembles Alima gracilis in the shape of its caqjus, while its 

 telson and the general outline of the body are so much like Faxon's larva as to indicate 

 that it is the young of a species of Squilla very closely related to Squilla nepa. A 

 number of specimens of this larva were collected by the Challenger on April 13, 1876, 

 near Sierra Leone. The carapace makes about half the total length of the body, and 

 it exposes the posterior end of the sixth thoracic somite, while the tips of its postero- 

 lateral spines, each of which has a small secondary spine about midway between the 

 base and the tip, extend backwards to the plane of the suture between the fiirst and 



(ZOOL. CHALL. EXP. — PART XLV. — 1886.) Yy 12 



