96 



U.S. NATIONAL MUSEUM BULLETEST 271 



Figure 45. — Haustoriidae: a,b, head, dorsal views showing small and large rostra (occa- 

 sionally genera occur with no rostra; those with large rostra (fig. b) have pereopod S like 

 fig. e, thus not shorter than pereopod 4; genera with large rostra and pereopod 5 like fig. / 

 are assigned to Phoxocephalidae); c, variational extremes in accessory flagellum [see 

 Ampeliscidae, Astyridae, Paramphithoidae]; d, pereopod 4, note spinosity and occasional 

 absence of article 7; e,f, extremes of pereopod 5, note spinosity [see Paramphithoidae]; 

 g,h, telsons; i, gnathopods highly variable but feeble [see most Gammaridae, Liljeborgiidae]. 



Ampeliscidae have amalgamated urosomites 2-3. Dogielinotidae lack mandibular palps 



and have a uniramous uropod 3. Astyridae have a characteristic lower lip. Argissidae have 



a special configuration of coxae 1^. 



