189!. 



PROCEEDINGS OF THE XATIONAL MFSEVM. 



519 



with median and niargiiial carina'; Hvo carinas on the carapa:e, its 

 anterior lateral angles produced into s[)ines and posterior corners 

 evenly rounded; lateral process of t!ic fifth tiioracic segment very 

 short, flattened antero posteriorly and obtuse, of the sixth and seventh 

 without spines and rounded; subniediau carinas on all segments of the 

 hind body behind the first exposed thoracic; the telson oruameuted 

 dorsally by a crest and curved lines of pits, and having six marginal 

 spines and a pair of anterior lateral carina', and on each side three to 

 four subraedian teetli, eight intermediate, and one lateral. 



General dcscripiion . — All tiie specimens of this species seen so far are 

 small. The carapace is rather short, being 0.2:3 of the total length and 

 seventeen-eighteenths of the gi-eatest width of the abdomen. The 

 greatest width of the carapace is about 0.77 of its length. The telson 

 on the other hand is relatively large and is broader than long, its 

 length being about 0.10 tlie total length and 0.92 or' its width at the 

 base. 



The <"irin;e on the rostrum (tig. 11) are small, but can be made out 

 distinctly with a lens. In the anterior fourth of the carapace the 

 median carina is obsolete or com- 

 pletely lost, bnt the lateral cai i- 

 ua3 pass directly into the ante- 

 rior lateral spines. Each of the 

 four exi)osed thoracic segments 

 (fig. 12) has four dorsal longitudi- 

 nal carina' except the first, Avhich 

 has no snbmedian ones. The lat- 

 eral process of the liflh segment 

 is drawn out into a very short ob- 

 tuse spine that is flattened ante- 

 ro-posteriorly and is connected 

 by a ridge with the short acute 

 ventral sj^ine of the same side. 

 The sixth and seventh segments 

 have on each side a broad, evenly ri.re^ tm.es n ,t„r,i ..zp. 



rounded, lateral lobe pointing 



oblicpiely a little backward. In front of this on the sixth segment 

 there is a slight projection common to most species of Sqnilla, bnt on 

 the seventh this projection is somewhat larger and flattened and 

 approaches the condition found in S. nepa. The eighth segment pos- 

 sesses a similar lobe. The carina^, of the abdomen, like those of the 

 thorax, are well developed. Xone of these end ui spines on the first, 

 second, and third abdominal segments, while all bnt the submedian ones 

 do so on the fourth, and all of them on the fifth and sixth. Besides the 

 six dorsal spines on the sixth segment there is a stout marginal spine 

 in front of each uropod. The telson has a low, sharp crest, ending in 

 a prominent spine and six small carina^ at the bases of the six marginal 

 spines, together with a pair of anterior lateral carime in front of the 



Fig. 11. 



riiPHALIC REGIO.V OF S(.)T-II.L.\ P.\RVA. 



