NEW MARINE ISOPODS^ — ^MENZIES 147 



Types.— Holotype male, allotype, and 5 male and 2 female para- 

 types collected at type locality, Tomales Bluff, Tomales Point, Marin 

 County, Calif., June 9, 1948, by R. J. Menzies; in rock and sand be- 

 tween coralline and laminarian algal zones; intertidal. Type ma- 

 terial has been deposited as follows : 



United States National Museum, holotype male. No. 87411; allo- 

 type, No. 87409 ; 1 male and 1 ovigerous female paratype, No. 87410. 

 Allan Hancock Foundation, 2 male paratypes. Pacific Marine Sta- 

 tion, 2 male and 1 fragmentary female paratypes, accession No. 1219 



Arth. 



Geographical distribution.— Knov^n only from the type locality. ^ 

 Remarks.— This species appears to be intermediate between A. hispi- 

 (fus Vanhoffen and A. charcoti Richardson (as figured by Hodgson 

 1910, pi. 9, figs. 1) . It differs from A. hispidus in having a bifurcat- 

 ing rostrum and pronounced preocular lobes. It differs from A. char- 

 coti in lacking a mandibular palp, in having an antennular flagellum 

 composed of three joints, preocular lobes that are not curved outward, 

 and a different-shaped pleotelson and uropods. 



Group JAEROPSINI " Nordenstam, 1933 

 Genus JAEROPSIS Koehler 

 JAEROPSIS DUBIA, new species 



Figures 29-33 



Eolotype.—ljQngih 2.8 mm., width at widest part of second per- 

 aeon somite 0.7 mm. 



Allotype.— Lq\\^\\ 2.3 mm., width 0.6 mm. 



Diagnosis.— BjQS located close to lateral margin. Anterolateral 

 angles of cephalon pointed, lacking deep anteriorly directed serra- 

 tions. Rostral process evenly curved and fringed with a delicate mar- 

 gin of wide scales. Maxilliped endite with three coupling hooks. 

 Both inner and outer distal angles of second joint of maxilliped palp 

 produced distally, inner angle bidentate. Pleotelson wdth a row of 

 five to seven spines on each lateral border. Between each pleotelson 

 spine is a row of three or four setae. Head generally heavily pig- 

 mented, body and abdominal segments very lightly pigmented or 

 without pigments. Penultimate joint of second antenna peduncle 

 with fringe of conspicuous scales on lateral margin. Exopodite of 

 uropods with two joints. 



Character of body.— Ammal appears elongate and flattened. 

 Many specimens have a wide median longitudinal thickening running 

 the length of the peraeon. In a few specimens the thickening is not 

 pronounced. Body smooth on dorsal surface, lacking any conspicu- 

 ous setae. Color variable with the following variations observed: 

 (1) Head black or brown, remainder of body brownish white; (2) 



^^ Considered by Nordenstam, p. 190, to be a new group of the family Parasellidae. 



