Color— Yellowish gray, light to dark brown, 

 or sometimes grayish, and mottled with dark gray 

 and/or white. Rhythmic chromatophore changes 

 as well as genetic differences may control observed 

 variations (McDermott, 1962). 



Habitat. — The species lives in burrows of 

 Arenicola cristata Stimpson (Wass, 1955; Mc- 

 Dermott, 1962), and possibly with other large 

 annelids ; shallow water to 20 fathoms. 



Type locality. — Jekyll Island, Ga. 



Known range. — North Falmouth, Mass., to Alli- 

 gator Harbor, Fla. 



Remarks. — McDermott (1962) summarized 

 existing knowledge of the habits of this species 

 and added numerous ecological observations. He 

 reported the crab for the first time from New 

 Jersey, finding it associated with 76 percent of the 

 lugworms collected during summer. Crabs and 

 worms were collected by manual digging. With 

 one exception, single crabs were found on worms. 



Of 18 female crabs found in July, 16 were ovig- 

 erous. One captive female produced eggs on July 

 7 and liberated zoeae "around" August 5. Crabs 

 which liberated zoeae when collected produced 

 new sponges of eggs which were in late stages of 

 development approximately 30 days later. Mc- 

 Dermott judged that this species produces at least 

 two egg masses in a breeding season. Molting be- 

 tween broods did not occur in the laboratory. 



Associates of P. cylindrica were found to be 

 Zoothammiwm sp., attached Crepidula convexa 

 Say, and colonies of Triticella elongata (Osburn). 



Pinnixa lunzi Glassell 



Figures 198-199 

 Pinnixa lunzi Glassell, 1937, p. 3, figs. 1-8. 



Recognition characters. — Carapace slightly 

 more than twice as wide as long, punctate, regions 

 indicated, borders flanged, with a shoulder 

 formed near wide lateral angle. Gastric and car- 

 diac regions separated by a depression connecting 

 with a deeper depression on each side of these re- 

 gions; a prominent cardiac ridge extending trans- 

 versely almost across carapace with an abrupt 

 slope from crest of ridge to posterior border. 

 Front prominent, bilobed, truncate, upturned over 

 antennules. 



Chelipeds stout; hands of male shorter and 

 stouter than in female, appearing disproportion- 

 ately small in female; palm with margins sub- 

 parallel in female, widest at base of dactyl in 

 n uile; in both sexes fingers gaping; immovable 

 finger horizontal, armed with row of small teeth, 

 distal tooth largest ; dactyl stout, curved, armed 

 with median lobe. Walking legs stout. First two 

 lightly crested with setae on merus; carpus crested 

 with a sharp beaded rim; propodus armed with a 

 row of fine, sharp, brown spinules; dactyls con- 

 torted, sharp pointed, fluted, with rows of small, 



Figure 198. — Pinnixa lunzi GlasseU. Male holotype in 

 dorsal view, 7 mm. indicated (after Glassell, 1937). 



Figure 199. — Pinni.m lunzi Glassell. A, right chela of 

 male ; B, right chela of female. 3 mm. indicated ; C. left 

 third walking leg of female, 4 mm. indicated; D, ab- 

 domen of female, 6 mm. indicated ; E, abdomen of male, 

 3 mm. indicated (after Glassell, 1937). 



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