18 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 



angulate with several spines on dorsal side. Pylopod with three segments 

 (third minute) ; whole medial margin with plumose setae. First walking 

 peraeopod with spine on ungus and series of tubercles along inner 

 margin of propodus. Both antennae shorter than cephalon ; first with 

 seven flagellar articles; second with five articles. Maxilliped with many 

 large plumose setae ; setae longer than width of segment on which lo- 

 cated. Mandible large, with lateral marginal notch and many well de- 

 fined teeth. From lateral view mandibles look especially large because 

 of deep cephalic pit. Pleopods with many plumose setae. Uropodal rami 

 with many long plumose setae ; endopod longer than telson. 



Measurements: Holotype male 3.5 mm long. 



Type locality: 6851; Coronado Canyon; 812 m; Feb. 1, 1960; 

 green mud. Lat. 32° 30' 42"x\, Long. 117° 21' 37"W. 



Materials examined: 6849 ( 1 ) ; 685 1 ( 1 ) . 



Distribution: Known only from the two specimens found in Coro- 

 nado Canyon. The second specimen was taken at 344 m in green mud 

 and gray mud with H2S smell. 



Affinities: The species differs from most of the other Gnathia in 

 the lack of conspicuous tubercles and hairs. The two specimens were 

 small uncalcified animals. 



Gnathia hirsuta, n, sp. 



(Plate 12) 

 Diagnosis: Eyes prominent, not stalked. Cephalon wider than long, 

 covered with many tubercles. Whole body, especially anterior segments 

 of peraeon, covered with long hairlike setae. Frontal margin of cephalon 

 with acutely rounded medial projection. Frons with some lateral crenula- 

 tions. Peraeonal segment one continuous in outline with cephalon, but 

 prominent only in mediolateral region. Hairlike setae also found on 

 basis of legs. Pleonal segments each with two (dorsolateral and ventro- 

 lateral) projections. Pleonal segment with stiff hairlike setae arising 

 from posterior margins of the segments. Telson long with two pairs of 

 setae, one near apex, another arising from apical margin. Pylopod tri- 

 articulate, apical segment minute ; medial margin fringed with long plu- 

 mose setae; ventral side covered with many long hairs. First walking 

 peraeopod with single spine on dactylus. Antennae one and two about as 

 long as cephalon ; antenna one with seven flagellar articles ; antenna two 

 with five articles. Maxilliped with many plumose setae along lateral 

 margin ; two coupling hooks on the blade. Mandible acutely pointed with 

 few teeth and without outer marginal notch. Pleopods without setae. 



