186 U.S. NATIONAL MUSEUM BULLETIN 271 



Because of its peculiar mandibular palp and immensely thickened 

 male antenna 2, Corophium, the type-genus, is not typical of most 

 other genera assigned to the family. Dr. E. L. Bousfield (in litt.) has 

 pointed out to me the probability that Ericthonius, with its elongate 

 peduncle of uropod 3, belongs with the Ischyroceridae. 



The Podoceridae differ from the Corophiidae by their elongate 

 urosomal segment 1. 



Corophiidae may resemble Eophliantidae and Colomastigidae be- 

 cause of their depressed, subcylindrical bodies and short, serially 

 gaping coxae but the latter two families have degraded mandibles. 



Nomenclatural Changes in Corophiidae 



Aorcho J. L. Barnard (1961) is removed to the Aoridae. 



Bogenfelsia J. L. Barnard (1962d) is removed to the Ischyroceridae. 



Dryopoides Stebbing (1888) was in Aoridae in Stebbing (1906) and 



transferred to Corophiidae by Stebbing (1910). Female keys ovit 



to the Aoridae. 

 Runanga J. L. Barnard (1961) removed from Podoceridae. 



Key to the Genera of Corophiidae 



(All species having gnathopod 1 larger than 2 should also be keyed out 

 in the Aoridae.) 



1. Uropod 3 lacking rami (fig. 80n) Concholestes 



Uropod 3 bearing 1-2 rami (figs. 80b-i) 2 



2. Mandibular palp 3-articulate (fig. 78^) 3 



Mandibular palp less than 3-articulate (figs. 78e,/) 21 



3. Inner ramus of uropod 3 distinct (fig. 80h) 4 



Inner ramus of uropod 3 absent or indistinct (uropod 3 with one ramus only) 



(figs. 806-sr) 7 



4. Coxae not touching serially (figs. 766,77a) 5 



Coxae touching serially (figs. 76c,d) 6 



5. Gnathopod 1 scarcely larger than and similar to gnathopod 2, palm smooth, 



inner ramus of uropod 3 distinct but much shorter than outer ramus (fig. 



80/i), third pleonal epimeron smoothly quadrate Camacho 



Gnathopod 1 much larger than 2, palm sculptured, inner ramus of uropod 3 

 usually represented by a large peduncular process (fig. 80i), rarely distinct 

 or marked off, when distinct scarcely shorter than outer ramus, third 

 pleonal epimeron bearing posteroventral tooth Unciola 



6. Inner ramus of uropod 3 much shorter than outer ramus, gnathopod 2 mero- 



chelate Paracorophium 



Rami of uropod 3 equally long, gnathopod 2 not merochelate. 



male of Dryopoides 



