186 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.10 



they have been shown to be uniquely asymmetrical (Ehlers, 1887, pi. 34, 

 fig. 6, Fauvel, 1917, pi. 6, fig. 54, and others) ; in this condition the first 

 plate on the left side is much smaller than maxilla II and very different 

 from the corresponding plate I on the right side (pi. 14, fig. 305). In 

 some other individuals the maxillae have been shown to be symmetrical 

 (Treadwell, 1921, fig. 422). A precisely similar condition has been 

 shown for A. symmetrica Fauvel (1914, pi. 7, fig. 4), which was first 

 thought to be merely a variety of A. fulgida but later (Fauvel, 1919, p. 

 388) erected to the rank of species. Unfortunately for this view, our col- 

 lections contain some interesting evidence on this controversy. 



Among the numerous collections listed above, the significance of this 

 character was sampled from 2 individuals taken at random from one of 

 the collections (473-35). In the first individual the maxillae were sym- 

 metrical, the parts as shown in pi. 14, fig. 304. In this the carriers are 

 long, slender, with median unpaired piece about as long as the paired 

 carriers, but wider. In the second individual from the same collection the 

 maxillary plates on the left side were strikingly different, the basal plate 

 (I) much the smaller, provided with numerous teeth at the cutting edge, 

 and plates II to IV provided with more numerous teeth than the com- 

 parable plates in the first individual. The unpaired carrier was the same. 

 The homologous plates, I to IV, in the 2 individuals, are strikingly dif- 

 ferent, but in all other respects the individuals compare favorably. They 

 are here considered to belong to a single species. 



A pair of mandibles (pi. 14, fig. 306), a median parapodium (pi. 14, 

 fig. 307), and a subacicular hook (pi. 14, fig. 303) are shown from an 

 individual with symmetrical maxillary plates. 



Distribution. — A. fulgida has been widely reported from Bermuda, 

 south through the West Indian region. In so far as I know, it has been 

 reported only once from the eastern Pacific, by Monro (1933, p. 91) 

 from Coiba Island, Panama, in 5-10 fms. These records indicate that it 

 may be common from the Gulf of California, south at least to Indepen- 

 dencia Bay, Peru. It is commonly intertidal; its greatest bathymetric 

 range, based on present records, is 22 fms. 



