88 



apex, and six-toothed below, the basal tooth large and much 

 curved. Feet spinulose ; the spinules on the third joint few and 

 distant. Length, 2.5 inches. Dredged in Puget Sound, by Capt. 

 Murden. 



Idot^ea resecata. Slender, convex above, thorax concave 

 below. Greatest breadth at the sixth thoracic segment. Outer 

 antennae reaching the fourth thoracic segment ; peduncle rather 

 stout; flagellum 17-articulate. Basal article of inner antennae 

 suborbicular, much expanded. Abdomen subrectangular, nearly 

 twice as long as broad ; posterior extremity with a deep con- 

 cavity, terminating on either side in a sharp angular projection 

 or spine. The first and second segments of abdomen sufficiently 

 well marked, the third also distinct on the sides ; — the three occu- 

 pying the anterior third of the length of the abdomen. Color 

 greenish yellow, with a median line of dark red. Length, 1.7 

 in. ; breadth, 0.33 in. It resembles I. hectica in general appear- 

 ance. Dredged in Puget Sound, by Capt. Murden. 



Lygia dilatata. Body variable in its proportions, but 

 usually very broad; the breadth to length being often as 1:1.5. 

 Surface granulated. Margins smooth, raised or thickened. Head 

 with a transverse ridge between the eyes, interrupted at the 

 middle. External antennae reaching the sixth segment ; flagel- 

 lum with 14 oblong articles. Caudal appendages very short, 

 about one fifth the length of the body ; basal article as broad as 

 long. Color, blackish. Length, 1£ inch. Found at Fort Steila- 

 coom, Puget Sound, by Dr. Suckley. 



Livoneca vulgaris. Variable in shape, often distorted ; 

 frequently abruptly widened at the fifth thoracic segment. Head 

 small, wider than long; inner antennae somewhat shorter and 

 stouter than the outer or posterior ones. Epimeral pieces nar- 

 row, separated from the tergal piece anteriorly by a distinct 

 suture, posteriorly by a deep incision ; the point reaching the 

 margin of the tergum in the anterior four segments, and not 

 extending much beyond it in the posterior three. Posterior 

 thoracic segment deeply sinuated for the reception of the middle 

 portion of the anterior abdominal segments. Lamelliform caudal 



