400 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ii5 



on hind margin. Coxal plate 3 with sides parallel, unevenly rounding 

 below, having several spinules on hind margin. Coxal plate 4 large, 

 with sinuous lower margin (fig. 4j). 



Pleon segments 2 and 3 with lower hind corner forming less than 

 right angle. Uropod 1 extending back slightly farther than 2, 2 

 slightly farther than 3. Peduncles of uropods 1 and 2 edged with fine 

 spines, but rami have few, if any, spines. Peduncle of uropod 3 with 

 3-4 spines on upper margin and 1 spine at distal end of first joint 

 of ramus. Telson reaching to about middle of peduncle of uropod 3 

 and bearing no spines. Length of male about 4 mm. 



Female. — Much like male, even in size. In gnathopod 2 defining 

 tooth of palm not so large; sinus of palm less deep with slight pro- 

 tuberance near middle. 



HoLOTYPE.— A male, USNM 94503, collected by E. F. Ricketts 

 from boat bottom, Monterey Bay, California, June 9, 1930. 



Remarks. — In the U.S. National Museum there are 6 specimens 

 from Monterey Bay and 2 specimens from Moss Beach, San Mateo 

 Co., California; 1 specimen from|Squaw|Island,fnear Coos Bay, 

 Oregon, and 1 specimen from South Bay, coast of Coos Bay. The 

 male and female figured are from Moss Beach and were collected by 

 W. H. Marshall, June 1, 1939. 



This species differs from Metopa esmarki Boeck (1872) from San 

 Francisco, California — transferred to Alesometopa by Gurjanova 

 (1951) — by the short fifth joint of gnathopod 1. 



Metopelloides diibia, new species 



Figure 5 



Male. — Head shorter than first 2 body segments combined; lateral 

 lobes rather prominent, evenly rounded; eye not visible. Antenna 1 

 reaching end of fourth joint off antenna 2; flagellum shorter than 

 peduncle and composed of about 16 joints. Antenna 2 more than K 

 length of body; third joint ji length of fourth, which is longer than 

 fifth; flagellum about as long as fifth peduncular joint and composed 

 of about 16 joints, first of which is long, appearing to be made up of 

 3-4 fused joints. 



Right mandible with rather broad toothed cuttmg-edge ; accessory plate 

 consisting of 4 knoblike spines, upper- one of wliich broadest, lowest 

 one narrowest (fig. 5d) ; spine row with about 18 rather blunt curved 

 spines; molar absent; palp 1-jointed, bearing 4 terminal and 3 lateral 

 spines (fig. 5c), Maxilla 1, inner plate lost in dissecting; outer plate 

 with 6 large teeth, 1 small tooth; palp 1-jointed, oblique distal end 

 armed with 13 terminal teeth and row of submarginal setae. Maxilla 

 2, inner plate shorter, narrower than outer, both very oblique distally, 

 edged with usual spines. Maxilliped, inner plate very small; outer 

 plate very small extension of inner margin of third joint, inner margin 



