182 U.S. NATIONAL MUSEUM BULLETIN 2 60 



Relationship. — This species has its closest affinities ^Yith the Pana- 

 manian Syrrhoites terceris J. L. Barnard (1964b). The two species 

 resemble each other in dorsal sculpture, pereopod 5, pleonal epimera, 

 and uropodal peduncles; however, S. terceris has long fifth articles 

 on the gnathopods, a deeply cleft telson, broader second articles of 

 pereopods 3 and 4, a slightly longer article 3 of the mandibular palp 

 and apparently no posterolateral process of pleonite 4, although the 

 latter may have been overlooked on S. terceris. 



Syrrhoites loalkeri Bonnier (1896) has a broad article 2 on pereo- 

 pods 3-5, a telson cleft halfway, an acute posterolateral process on 

 pleonite 4, but it resembles S. redox in the short fifth articles of the 

 gnathopods and in general sculpture, except for the absence of a 

 tooth on pleonal epimeron 2. 



The female of this species is closely related to S. tnix., new species, 

 but differs by the narrower second articles of pereopods 3 and 4, the 

 posteroventrally quadrate article 2 of pereopod 5, the short cleft of 

 the telson, the short article 3 of the mandibular palp, the shorter fifth 

 articles of the gnathopods, the blunt, not acute, posterolateral proc- 

 ess of pleonite 4, the subacute anterolateral cephalic corner and the 

 absence of lateral peduncular processes on uropods 1 and 2. 



Syrrhoites cohasseta., new species, resembles S. redox but has a 

 smaller dorsal tooth on pleonite 3, no distinct postero ventral tooth on 

 pleonal epimeron 2, a rounded (not quadrate) posteroventral corner 

 of article 2 on pereopod 5 and also differs by the other characters men- 

 tioned above for S. trux. 



Syrrhoites didcis, new species, and S. silex^ new species, have deep 

 telsonic clefts, lateral uropodal processes, and broader second articles 

 of pereopods 3 and 4 than does S. redox. 



The male assigned provisionally to this species is so remarkabl}^ 

 different from the female that its nomenclature must remain ques- 

 tionable until the life history of the species can be studied. The 

 similarities of male and female in dorsal sculpture, pleonal epimera, 

 head and telson justify the provisional assignment of the male to 

 S. redox. Sexual dimorphism of antennae and pleonal processes occur 

 in this genus and its relatives but the striking conditions of the dorsal 

 tooth of pleonite 3, width and serrations of article 2 on pereopod 5, 

 and the serrations occurring on pleonal epimeron 3 are distinctions of 

 considerable magnitude. 



This male resembles the female of S. silex, new species, in the occur- 

 rence of serrations on pleonal epimeron 3 but the dorsal tooth of 

 pleonite 5 is especially incongruent, article 3 of the mandibular palp 

 is particularly short in the male at hand, and S. silex has lateral 

 peduncular processes on uropods 1 and 2. The shapes of the postero- 



