fifth thoracic sternum nearby. (Modified after 

 Alcock, 1896, in Rathbun, 1937.) 



Family Leucosiidae 



Crabs having carapace circular, oval, or polyg- 

 onal. Eyes and orbits small, front narrow but 

 wider than orbit. Antennules folding more or less 

 obliquely. Antennae small. External maxillipeds 

 completely enclosing buccal cavity, except often 

 a small crevice in front. Afferent branchial chan- 

 nels occupying sides of endostome on either side 

 of deep, median, endostomal groove serving as an 

 efferent branchial channel. Afferent channels 

 covered by exognaths of external (third) maxilli- 

 peds, efferent channels by a pair of lamellar proc- 

 esses of first maxillipeds. Chelipeds symmetrical. 

 Abdomen hidden beneath thorax, commonly with 

 third to sixth abdominal terga fused, sixth some- 

 times free. Vasa deferentia opening on fifth 

 thoracic sternum near bases of last pair of legs. 

 (Modified after Alcock, 1896, in Rathbun, 1937.) 



KEY TO GENERA AND SOME SPECIES IN THE 

 CAROLINA S 



a. Carapace polygonal, uneven, nodular, or eroded 



Subfamily Ebaliinae (p. 147). 

 b. Posterior portion of carapace without deep cavities 



Ebalia cariosa (p. 147). 

 bb. Posterior portion of carapace with a deep rounded 



cavity on each side Spetoeophorus (p. 148). 



aa. Carapace ovoid or globular, and smooth or granular 

 Subfamily Philyrinae (p. 150). 

 b. Fingers opening in horizontal plane 



Persephona punctata aguilonaris (p. 150). 

 bb. Fingers opening in vertical plane 



Iliacantha (p. 150). 



Subfamily Ebaliinae 



Surface of carapace uneven. Chelipeds of mod- 

 erate length; fingers not very thin and elongate, 

 dactyl moving in an oblique plane. Anterior mar- 

 gin of buccal cavity arcuate, middle part in front 

 of level of anterior pterygostomian region. Epi- 

 stome and infraorbital lobe well developed. Ptery- 

 gostomian margin extending either slightly or dis- 

 tinctly forward, terminating in an indentation. 

 Merus of external maxillipeds half or more than 

 half length of ischium measured along inner bor- 

 der. First abdominal segment in female often 

 under carapace (Rathbun, 1937). 



Genus Ebalia Leach, [1817] 



Rathbun, 1937, p. 123. — Hemming, 1958b, p. 15. 

 Ebalia cariosa (Stimpson) 



Figure 122 



Lithadia cariosa Stimpson, 1860a, p. 238. — Hay and Shore, 

 1918, p. 424, pi. 32, fig. 6. 



Ebalia cariosa: Rathbun, 1937, p. 125, pi. 35. figs. 6-7 (rev.). 



Figure 122. — Ebalia cariosa (Stimpson). Animal in dor- 

 sal view, legs of left side not shown, 3 mm. indicated. 



Recognition characters. — Carapace convex, 

 roughly pentagonal; anterior angle truncate, lat- 

 eral angles obtuse; surface uneven and covered 

 everywhere, including other parts of body and 

 legs, with beadlike granules, larger posteriorly 

 and ventrally. Front narrow, upturned, and 

 broadly notched, connected with middle protuber- 

 ances by a median ridge traversing gastric region ; 

 ridge flanked on each side by a sinuous, deep, 

 broad excavation of darker color than protuberant 

 parts. Anterolateral margin of hepatic region 

 sinuous, hepatic region slightly prominent, de- 

 limited posteriorly by an impressed line. Ptery- 

 gostomian region with a large downward-point- 

 ing tooth, hardly visible in dorsal view. Postero- 

 lateral margin with a broad tooth, separated from 

 bilobate intestinal region by a deep sinus; cardiac 

 and inner lobules of branchial region strongly 

 protuberant, separated from thick intestinal lobes 

 by a deep narrow sulcus. 



MARINE DECAPOD CRUSTACEANS OF THE CAROLINAS 



147 



