fc> 



18 Carl Bovallius, 



The fifth to seventh pairs are like those of S. ultramarina, dif- 

 fering only in the form of the femora of the fifth and sixth pairs. 



The pleon is longer than the pereion. 



The peduncles of the pleopoda are cylindrical, shorter than the 

 flagella. 



The urus. The first segment is three times longer than the se- 

 cond, the third is almost twice longer than the same. 



The fiî'st pair of uropoda [PI. II, fig. 29]. The outer ramus is 

 finely ciliated along the inner margin, with a minute spine in the middle. 



The second pair. The peduncle reaches beyond the posterior mar- 

 gin of the last segment. The outer ramus is totally smooth along both 

 margins; the inner ramus finely ciliated, with two short spines along 

 the inner margin. 



The third pair. The rami are unequal in length, the outer the 

 longest, two-jointed ; the outer margins of both rami are smooth, the 

 inner fringed with hairs along their whole length. 



The telson is a little longer than the last ural segment, broadly 

 ovate, bifid, with rounded ends, the fissure scarcely equalling half the 

 length of the telson. 



Colour. Hyaline. 



Length. 4 — 6 m.m. 



Hab. The tropical parts of the Atlantic (U.M. S.M.). Some 

 twenty miles East off" Barbadoes (D.M., O.B.). 



4. Synopia gracilis. DANA, 1852. 



(PI. II, fig. 31—35, copied from Dana). 



Syn. 1853. Synopia gracilis. DANA. United States Exploring Expedition. Crustacea. 



vol. 2, p. 998. pi. 68, fig. 7 a— e. Fol. 



Diagn. Caput trianguläre, longitudine latitudinem sequans. 

 Oculi supplementarii desiint. 

 Antennœ primi paris quam pereion multo longiore.s; flagellum secundarium 



longitudine ai'ticulum primum flageUi (veri) sequans. 

 Segmentum primum pereii secundo brevius, segmentum sextum et septimum 



sequalia. 

 Femora parium quinti et sexti pedum pereii non rotundata, infra truncata. 



Pedes septimi paris pedibus sexti paris longitudine œquales. 



