﻿156 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 102 



70, c), not directed abruptly posteriorly. A very small species, the 

 adults being only slightly longer than postembryonic larvae of most 

 species (e. g., specimens lacking developed seventh pair of peraeo- 

 pods). 



Character of hody. — Small, with few scattered black chromato- 

 phores. Anterior part of cephalon with many black chromatophores. 



Pleotclson. — Ovoid, with evident anterolateral angles, posterolateral 

 angles lacking. Posterior border with short median convexity. 



Second anteoi7iae. — Not so long as body. Flagellum with 27-32 

 subequal articles. 



Maxillifed. — Those of male and female similar. 



First maxilla. — Outer lobe with 13 setae, inner lobe with 3 setae. 



Second nnaxilla. — Each of the two outer lobe lappets with four setae, 

 inner lobe with about eight setae. 



Mandible. — Left mandible incisor with five teeth, lacinia with five 

 teeth, setal row with five setae. Right mandible incisor with five 

 teeth, lacinia lacking, setal row with five setae. Second joint of palp 

 with only two denticulate setae near distal end on inner margin. 



Peraeopods. — Similar to those of /. h. kincaidi but sparsely setose in 

 comparison. 



Types.— T\\Q holotype (U.S.N.M. No. 89522), allotype, and 2 

 paratypes were collected at the type locality, Dillon Beach, Second 

 Sled Road, Marin County, Calif., October 6, 1948, by R. J. Menzies ; 

 mid-intertidal, under rock. All are in the collection of the United 

 States National Museum. 



Geographical distribution. — Known only from Marin County, Calif. 



Material examined. — Tomales Point reef, Marin County, Calif., 1 

 male paratype June 9, 1949, R. J. Menzies, collector, mid-intertidal 

 zone among rock and sand. 



Ecology. — ^Mid-intertidal, under rock and sand. 



lANIROPSIS TRIDENS, new species 



Figure 71 



Holotype. — Male, length 2.5 mm., width 0.6 mm. 



Allotype. — Not ovigerous, length 1.5 mm., width 0.5 mm. 



Diagnosis. — Frontal margin of cephalon with a very slight median 

 convexity. Each lateral (posterior half) border of pleotelson with 

 three spinelike serrations. First antennal flagellum with nine articles 

 (adult). Each lateral apex of first male pleopod directed posteriorly 

 but apparently not as abruptly as in /. epilittoraVis (compare figs. 67, e 

 and 71, e) . Uropods exceeding half the pleotelson length. 



Character of body. — Chromatophores scattered irregidarly over 

 body. Eyes red in life. 



Pleotelson. — Postei'ior border with an evident median lobe. 



