462 STALK-EYED CRUSTACEA 



I. Alpheus armillatus. 



Alphcus annlllatus ... H. Milne Edwards. 



AlpJuus JieterocJieles . . . Say, Kingsley. 



Alphcus lutarijis 1 „ 



. r . . . baussure, 

 Ilalopsyclie hit ana) 



Carapace smooth. Rostrum short, acute, depressed ; 

 ocular arches without spines. Basal spine of internal 

 antennae stout, short, not reaching base of 'second joint ; 

 second joint more than twice as long as third. Outer 

 flagellum half as long as inner. Antennal scale as long 

 as peduncle of the internal antennae ; the spine on the 

 anterior lateral margin large, stout, acute ; inner margin 

 arcuate, widening towards the base ; flagellum somewhat 

 longer than the body. Legs of the first pair unequal ; 

 fourth joint triangular ; fifth as broad as long ; larger hand 

 one and a half times as long as carapace, compressed, 

 margins rounded ; a constriction of the upper and under 

 margins at about the middle. Fixed finger three-fourths 

 as long as palmar portion ; a strong rectangular tooth on 

 inner portion of occludent margin ; apex acute. Movable 

 finger with a process on the inner margin which shuts 

 into a cavity in the opposing finger ; points of fingers 

 overlapping. The smaller hand cylindrical, the constric- 

 tions but faintly indicated ; fingers three-fourths as long as 

 palm. Movable finger flattened ; occludent margin with 

 a longitudinal carina, shutting into a groove in the fixed 

 finger; the fingers with a fringe of hair. Legs of the 

 second pair slender, filiform ; third and fourth joint equal ; 

 fifth joint five-jointed*; first joint as long as second and 

 third, second as fourth and fifth, third and fourth equal, 

 fifth a half longer than preceding. Telson subquadrate ; 

 extremity arcuate. 



