THE BRACHYURA AND MACRURA OF PORTO RICO. 
77 
but smaller; flagellum very small. Carapace oblong-oval, antero-lateral and postero-lateral borders 
forming together a slightly arcuate line. Merus of outer maxillipeds dilated outwardly and very 
slightly notched on inner side for insertion of palpus. Chelipeds with fingers spoon-shaped; hands 
more or less compressed. Ambulatory legs stout and rather short; dactyli sharp and spinulous below. 
Abdomen of male narrow and formed of seven articles. Straight, stiff hairs border the antenna* and 
are arranged in a series of tufts on the ptervgostomian regions. 
Key to the Porto Rican species of the genus Pitho. 
A. Antero-lateral teeth obtuse (in the adult); second antennal segment with its outer lobe strongly produced 
laterally aculeate i 
A'. Antero-lateral teeth acute. 
B. Carapace covered with granules tipped with hairs; lateral teeth diminishing in size from the first to last, 
the second and third not united at base mirabilis 
B'. Carapace with no conspicuous granules. Lateral teeth not diminishing in size from the first to last, sec- 
ond and third more or less united at base. 
C. Second lateral tooth much reduced. Carapace almost smooth. Chelipeds of adult male very elongate, 
cylindrical anisodon 
O'. Second lateral tooth but slightly reduced. Carapace tubereulate. Chelipeds of adult male less elongate, 
broad , heavy Iherminieri 
An “ Othonia nova species, von Martens,” is recorded by Gundlach from Aguadilla; 
one of the above species. 
Pitho aculeata (Gibbes). 
it. may be 
Ilyas aculeata Gibbes, Proc. Amer. Assoc. Adv. Sci., in, 171, '1850. 
Othonia aculeata Stimpson, Ann. Lye. Nat. Hist. N. Y., VII, 49, 1859; Ratlibun, Proc. U. S. Nat. Mus., XV, 255, pi. xxxiv, 
figs. 1 and 2, 1892. 
Pitho aculeata Rathbun, Ann. Inst. Jamaica, I, 7, 1897. 
Carapace a little longer than broad, almost smooth above in adult, more or less tuberculous and 
granulous in young. Width between outer orbital angles two-thirds of entire width. Preorbital and 
external orbital angles subacute. Antero-lateral margins armed with five teeth (exclusive of orbital 
angle) more or less triangular, obtuse in the old, acute in young, the second and third coalesced at 
their base, the fourth and fifth small. Frontal teeth small, flat, triangular, obtuse. Basal article of 
antennae wide; that portion of its anterior margin situated outside of the insertion of the second article 
is denticulate; a deep groove between this crest and frontal border, a second groove on the carapace 
parallel to first. Second article with an outer lobe much produced laterally. Chelipeds strong in the 
full-grown male, about!. 5 times as long as carapace; arm angular, with three depressed tubercles on 
upper margin; wrist with a smooth longitudinal crest; palms compressed, about 1.5 times as long as 
wide; fingers widely gaping for their distal two-thirds, with a tooth near base of dactyl. Chelipeds in 
the young male and in the female short and weak; fingers evenly dentate and in contact. The carpal 
joints of the ambulatory legs have a broad, deep groove on the outer surface. Appendages of first 
segment of abdomen in the male are brown in color for their distal half, the brown parts in contact 
for half their length, diverging at extremities in slight curves convex to each other, each appendage 
terminating in a right-angled hook, the point of which is directed toward median line of carapace. 
Dimensions of male: Length, 27.5 mm.; width, 26 mm.; width across orbits, 17 mm. 
Florida Keys; Bahamas; West Indies. Porto Rico: Boqueron Bay; Culebra. 
Pitho anisodon (von Martens). 
Othonia anisodon \ on Martens, Arch. f. Natur. , xxxvin, 83, pi. iv, f. 3, 1872. 
Othonia Iherminieri Rathbun, Proc. TJ. S. Nat. Mus., xv, 255, pi. xxxiv, figs. 3 and 4, 1892. (Not 0. Iherminieri Schramm.) 
Pitho anisodon Rathbun, Ann. Inst. Jamaica, I, 8, 1897. 
Allied to P. aculeata. Front much narrower, width between outer orbital angles but little more 
than half the entire width; rostrum more advanced and less deflexed. A slighter groove runs from tip 
of inner upper angle of orbit to base of rostrum. Orbital angles less advanced and less conspicuous, 
though more acute. Second article of antenna with a shorter outer lobe, directed forward. Antero- 
lateral teeth sharp, the last two of good size, the second much reduced. Carapace smoother and more 
