288 PROCEEDINGS OF THE NATIONAL MUSEUM. 



siiio-h^ .spine, which stands out diaoonally and curves forward. The 

 areolations arc very protuberant; three spines arise from the i^astric 

 area, a transverse pair near the front and one on the median line 

 farther back. There is a hxrge spine on the cardiac area, foHowed by 

 one or more smaller ones; three spines on the post-branchial area are 

 in line near the margin; behind the antero-latoi-al angles there are 

 three spines on the margin. The posterior border is armed with six or 



Fig. ;;i. — Munidopsis opalescens, L'f. 



more spines. In addition to the spines enumerated there are a variable 

 number of spinules and spiny granules scattered over the surface. 



The second segment of the abdomen is armed with two large spines; 

 anterior to these at the sides are one or more paired spinules. The 

 third segment is armed with four spines, a pair on each of the two 

 ridges; the anterior pair are the larger. The inferior margin of the 

 merus of the maxillipeds is armed with four spines, the third is 

 usually the shortest; the superior margin has three or four snmll 

 denticles. 



