GOO PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxi 



POTAMONlDiE. 

 104. PSEUDOTHELPHUSA DENTATA (Milne-Edwards). 



Thelphusa denlaia I.atijkillk, Kncyc AKth., Hist. N:ik, Entoiii., 1825, X, p. 501. 

 rscudothclplniHu dimiala Smitii, TrariH. Conn. Acad. iSci., 1870, II, p. 117 



Port Castries, St. Ijucia. 



PALICID^^l 



' 105. PALICUS ZONATUS Rathbun. 



CymopoHa sonata Raiiihun, I'roc. U, S. Nat Mus., 1893, XVI, p. 259. 

 PalicHs zonatiis Katiihi'n, Pioc. Biol. Soc. Washington, 1897, XI, ]). 94. 



Southern part of Gulf of California, 8 to 10 fathoms, stations 2824, 

 2827, 2828; off Cape St. Lucas, 31 fathoms, station 2829. 



106. PALICUS LUCASII, new species. 

 (PlateXLIII, lig. 2.) 



Lenf/ih of second ambulatory le<i Ichh than tirice the width of the cara- 

 pace. Abdomen and sternum not conspicuously cristate. Antero lateral 

 teeth two, besides the orbital. Anterior margin of second and third 

 ambulatory legs terminating in an acute or subacute tooth, not spiniform. 



Allied to /'. dentatus, faxoni and alternatus of the West Indian 

 region. 



Carapace broad, subquadrate. The clusters of tubercles on the sur 

 face are well marked and distinct from one another; those on the cardiac 

 and intestinal regions have a short transverse crest. The surface 

 between the clusters is covered with granules barely visible to the 

 naked eye. Frontal lobes or teeth four, the median pair small and 

 rounded and separated by a narrow rounded sinus more than twice as 

 deep as those dividing the median from the lateral i)air; these last have 

 an oblique arcuate outer margin. The preorbital lobe is slightly bilobcd 

 by an indentation at its summit. The two supraorbital teeth are trian 

 gular and subacute. The postorbital tooth is directed forward; behind 

 it, on the lateral margin, are two large acute teeth, with straight inner 

 margins; outer margins slightly arcuate. These teeth are followed by 

 one or more denticles. The crest above the posterior margin is cut into 

 four long and three short transversely linear tubercles. Suborbital 

 lobe truncate, not advanced, and separated on either side by a V-shaped 

 fissure. The lobe at the angle of the buccal cavity is triangular, and 

 in a ventral view oidy partially obscures the truncate inner suborbital 

 lobe. Basal joint of the antenna cut by a deep U-shaped sinus into 

 two lobes, the inner and inferior small and tuberculiform, the outer and 

 superior broad and lobiform. 



The right chelipt'd of the male is very heavy. Merus spinulous. 

 Carpus with about four superior spines and a number of spmules, an 

 inner spine, a spinulous antero-internal crest, a right-angled antero- 



