g32 CRUSTACEA. 



3. Styli caudales 3tii parvuli, biramei, ramo externo non uncinate, 2di \mique ramis 

 extus non praecipue spinosis nee cidtriformibus. 



G. 5. Unciola, Say* — Pedes lmi 2dique manu confecti, lmis validioribus. An- 

 tennae flagellis confectae, subpediformes, validae, superiores paulo longiores, ap- 

 pendiculatae. 



4. Styli caudales Ztii paulo elongati, biramei, ramo externo uncinate. 



G. 6. Podocerus, Leach.^ — Pedes lmi 2dique Bubchelati, 2dis validioribus. An- 

 tennae superiores breviores, non appendiculatae. [An maris digitus 2dus interdum 

 2-articulatus, Kroyer teste.] 



G. 7. Cratophium, Dana. — Pedes lmi 2dique subchelati, 2dis validioribus. An- 

 tennae superiores breviores, appendiculatae. 



B. Digitus 2dtjs 2-articulatus. 



G. 8. Cerapus, Say. — Antennae pediformes, subaequae, flagellis carentes. Pedes 

 lmi 2dique prehensiles, lmis parvulis, 2dis manu bene confectis. Styli caudales 

 3tii biramei, ramis subaequis, longiusculis. [Tubum membranaceum inhabitat.] 



G. 9. Cerapodina, Edw. {Cerapus, Templeton.) Antennae totae flagellis con- 

 fectae. Pedes 4ti 5ti 6tique obsoleti (?). [Tubum papyraceum inhabitat.] 



G. 10. Erichthonius, Edw.\ — Antennae flagellis confectae. Pedes 10 postici 



* Jour. Acad. Nat. Sci. Philad., i. 388. 



Glauconome of Kroyer has the hands and antennae and apparently the other cha- 

 racters of Unciola. Say describes the hands of the second pair in Unciola as adactyle; 

 but they still are probably like those of Glauconome. The following is Kroyer' s de- 

 scription : — 



"Antennae subpediformes; superiores flagello ornatae appendicular! perparvo. Oculi 

 minuti, parum distincti. Mandibulae apex in duos fissus ramos qui dentibus sunt 

 armati conicis ; tuberculus molaris dentibus confertissimis instructus. Labium superius 

 breve, depressum latissimum, margine anteriori medio inciso ; labium in/erius quatuor 

 compositum laminis setosis. Laminae maxillares pedum maxillarium dentibus armatae 

 validisj unguis palpi apice setosus. Pes primi paris robustissimus, manu subeheli- 

 formi ; pes secundi paris gracilior, manu carens subcheliformi, pedes 3tii 4tique paris 

 pergraciles; pedes 5ti 6ti 7mique paris graciles femoribus parum dilatatis. Pedes 

 abdominales lmi 2di et 3tii paris natatorii, breves sed robustissimi; 4ti 5tique paris 

 saltatorii, validi ; 6ti paris fere rudimentares, natatorii. Epimera minima fere evanes- 

 centia." 



f Jassa of Leach may, without inconvenience, be united to Podocerus, as there is no 

 essential generic difference between them. 



% The author obtained three species in the cruise of the Expedition having the hands 



