THE BRACHYURA AND MAGRURA OF PORTO RICO. 
41 
margins convex, spinulous; a small spine or spinule on tooth forming the outer angle, although Miers 
says this is obsolete. Orbital margin spinulous; inner half of lower margin spinous. Upper and outer 
surface of chelipeds clothed with spines, covering the palms (where they are arranged in longitudinal 
series) and basal portion of dactyli. Legs spinous above. 
Dimensions of female: Length, 6 mm.; width, 7.7 mm. 
Off Bahia, Brazil, 7 to 20 fathoms (type locality). Porto Rico: Off Vieques, 6 to 16 fathoms, 
stations 6085, 6091, 6092, 6096; off Culebra, 14f fathoms, station 6086. 
Pilumnus marshi, 1 sp. nov. 
This species in its general appearance is so like I J . brasiliensis that at first glance one might take 
them to be the same. The carapace is, however, narrower, and the antero-lateral margin shorter, 
being only a little more than half the length of postero-lateral margin, whereas in P. brasiliensis the 
antero-lateral is nearly as long as the postero-lateral. There 
are only three lateral spines in our species, the spine at the 
outer angle of orbit being absent. The posterior of the spines 
is small and appressed, while in P. brasiliensis it is similar in 
size and direction to the other spines. The corneal extremity 
of the eye is much larger in our species. Fingers of cheli- 
peds longer and more deeply grooved. Legs considerably 
longer than in the allied species; for example, the merus of 
last pair when flexed reaches farther forward than tip of 
penult antero-lateral spine; in P. brasiliensis the same joint 
fails to reach tip of posterior spine. 
Length of male, 5.5 mm.; width, 7 mm. Length of 
female, 5.7 mm.; width, 7.1 mm. 
Type locality, off St. Thomas, 20 to 23 fathoms, station 6079, 1 male (Cat. No. 23771 ). Also taken 
at the next station, 6080, near the last, in 20 fathoms, 1 female. 
Fig. 8. — Pilumnus marshi , male, (a) Carapace, 
x 4. (6) Large chela, x 4. 
Genus EURYTIUM Stimpson. 
Eurytium Stimpson, Ann. Lyc. Nat. Hist. N. Y., vri, 56, 1859. 
Carapace broad (length about two-thirds width), convex, regions lightly marked, without trans- 
verse raised lines. Antero-lateral borders regularly arcuate, shorter than postero-lateral, cut into five 
shallow teeth, the second tooth rounded and intimately fused with first. Fronto-orbital border over 
half the width of carapace. Front from a fourth to almost a third the width of carapace. Front 
deflexed, two rounded lobes separated by a shallow notch. Superior margin of orbit with two short 
and inconspicuous fissures; lower margin with a deep rounded sinus outside, and two lobes, of which 
the inner and smaller is slightly more advanced than outer. Basal antennal joint broad and in 
contact with front; the flagellum stands in orbital hiatus. The ridge on the endostome which defines 
the efferent branchial channel is well marked, and continued to margin of epistome. Chelipeds 
massive and rounded, unequal in both sexes. The abdomen in male is fr T e-jointed. 
Allied to Eupanopeus, Eurypanopeus, etc., but distinguished by its oval and almost smooth 
carapace, without ridges, and by its palatal ridge. 
Eurytium limosum (Say). 
Cancer limosa Say, Jour. Phila. Acad. Sci., I, 446, 1817. 
Panopeus limosus Milne Edwards, Hist. Nat. Crust., i, 404, 1834. 
Eurytium limosum Stimpson, Ann. Lyc. Nat. Hist. N. Y., vu, 56, 1859; A. Milne Edwards, Crust. R<*g. Mex., 332, pi. lx, 
f. 2, 1880. 
Carapace very convex in an antero-posterior direction; surface smooth to eye, but under lens gran- 
ulate, the granules coarser near frontal and antero-lateral margins; two feeble epigastric lobes. Front 
one-fourth the width of carapace. Antero-lateral margin about two-thirds the length of postero-lateral, 
bordered by a raised line of granules; second tooth lobiform, separated from first by a shallow sinus; 
1 In honor of Mr. M. C. Marsh, one of the naturalists of the expedition to Porto Rico. 
