250 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 18 



combined. Ratio of widths of articles 2, 4, 5, 6 = 23 :11 :7:3. 



Peraeopod 5: article 2 broadly expanded, in one form the ratio of 

 width to length being as much as 61 :56 while in the other major form 

 it is as little as 47 :56. Article 2 varies in its downward extension from 

 about midway almost to the end of article 4. The sweep point varies 

 in position from above the base of article 3 down to its distal end; in 

 the former extreme, the lower edge of article 2 is much more rounded. 

 The teeth on the posterior edge are very small, generally 9 in number, 

 in some specimens being nearly obliterated. Article 6 is slightly longer 

 than either 4 or 5. 



Uropod 1 : lateral peduncular margin with moderately stout spines, 

 rami shorter than peduncle, each armed with a variable number of 

 marginal spines, those on the inner ramus being smaller than those 

 on the outer ramus. Each ramus has a terminal spine. 



Uropod 2 : peduncle bears spines, ranging from very slender to 

 very stout in the extremes; outer ramus about as long as peduncle, 

 bearing several stout or slender spines; inner ramus unarmed. Each 

 ramus has a terminal spine ( see Table 5 ) . 



Uropod 3 : inner ramus longer than half the length of the outer, 

 in its maximum development as long as article 1 of outer ramus; 

 article 2 of outer ramus stout, one fifth to one seventh as long as article 1. 



Telson broad, apices blunt, slightly oblique, armed with 3 spines, 

 lateral margins with spines at distal third. 



Third epimeron varying from a form having a concave posterior edge 

 and a slightly upturned lower corner to one having the posterior edge 

 straight and the lower corner evenly rounded. The setae on the posterior 

 edge vary from few to numerous (See Table 5). 



Male. — Sexual dimorphism typical. 



Discussion. — This species is quite abundant and widely distributed in 

 the eastern Pacific Ocean ; it is quite variable so that a limited diagnosis 

 is difficult. For this reason I have employed a large number of figures 

 in order to record the variations encountered. 



PLATE 32 

 Paraphoxus obtusidens (Alderman) major n. subsp., female, 12 mm, Sta. 888-38. 



Figs. A,B, antenna 1, 2; C, head; D, epistome; E, mandible; F, lower 



lip; G,H, maxillae 1, 2; I, maxilliped; J, coxa 1; K, gnathopod 2; 



L,M, gnathopods 1, 2; N,0,P,Q, peraeopods 2, 3, 4, 5; 



R,S,T, uropods 1, 2, 3; U, telson; V, pleon segments 3-2. 



Male, 7 mm, Sta. 2018-51. Figs. W, head; X, antenna 2; Y, uropod 3; Z, telson. 



