STALK-EYED CRUSTACEA 393 



a. Colour brick-red. The surface when magnified 

 shows many punctures. — (P. luagnifica^ 



b. Teeth on inner margin of fifth joint of both legs.- — 

 i^P. annatus?) 



c. Teeth on inner margin of fifth joint of left anterior 

 leg. — {P. viarginatus^ 



B. Inner border of fifth joint of first pair of legs 

 without spines or teeth.- — (P. tridoitatus}) 



I. Petrolisthes magnifica. 



PetrolistJies uiagnifica . . Gibbes, Benedict. 



PetrolistJies politus . . . Stimpson. 



PorceUana polita .... Gray. 



Porcellana magnifica . . . Gibbes. 



When the surface is magnified many punctures are 

 seen, the position of each puncture being marked by a 

 very small light coloured spot. The fourth joint of the 

 walking legs is coloured the same as the carapace. The 

 fifth joint is darker. The sixth joint is a deep red, 

 darkest near the distal end, which is abruptly light. The 

 terminal joint is light, each with a deep red ring in the 

 middle. First pair of legs, a deeper red than the carapace, 

 has spines on inner border of fifth joint. The tips of the 

 finger are crimson, with subterminal portion black. Cara- 

 pace brick-red. 



Range. — Barbados, St. Thomas ; found under stones 

 on the shore. 



2. Petrolisthes armatus. 



PetrolistJies armatus . Gibbs, Stimpson, Henderson. 

 Porcellana armata . . Gibbs. 



The inner border of the fifth joint of the first pair of 

 legs has three or four spines. The outer edge of the hand 



