388 



U.S. NATIONAL MUSEUM BULLETIN 271 



Relationship." — -The Stenothoidae, Cressidae, and Thaumatel- 

 sonidae have enlarged coxae 2-4, more elongate telsons than do 

 Pagetinidae and coxa 1 is small and hidden by the following coxae. 



The Pardaliscidae have biramous third uropods. 



The Eophliantidae and Phliantidae lack mandibular palps, the 

 former having cylindrical bodies, the latter having depressed bodies. 



The Pagetinidae bear some resemblance to Sebidae in mouthparts, 

 uropods, telson, and coxae but Sebidae have chelate gnathopods, 

 elongate third artcles of gnathopod 2 (with one exception) and 

 well-formed plates of the maxillipeds. 



Key to the Genera of Pagetinidae 



These genera, possibly synonymous, are based on characters which 

 may be conditions due to different methods of preservation, mounting 

 technique, and observation. 



Figure 139. — Pagetinidae: a, head and gnathopod 1 of Pagetina genarum K. H. Barnard 

 (1932). Upper lip: b, Heterocressa monodi Nicholls (1938). Mandible: c, Heterocressa. 

 Maxilla 1 : d, Pagetina, e, Heterocressa. Maxilliped : /, Pagetina; g, Heterocressa. Perec- 

 pods 1,3,5: h,j,k, Pagetina. Gnathopod 2: i, Pagetina. I, Pagetina, dorsal view of tel- 

 son and uropod 3. Uropod 3: m, Heterocressa. Telson: n, Heterocressa. Lower lip: 

 0, Pagetina. 



