THE BRACHYURA AND MACRURA OF PORTO RICO. 
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Family PANDALID^E Kingsley, 1878 (Pamlalinae); Bate, 1888. 
Rostrum long and slender, armed with teeth or spines. Eyes well developed. Mandibles with 
a two or three-jointed palp. First pair of trunk-legs not chelate, second pair chelate, carpus sub- 
divided. Pleopods biramous; tail-fan well developed and strong. 
Key to the Porto Rican genera of the family Pandalidfe. 
A. Rostrum not articulated with frontal margin of carapace Pandalus 
A'. Rostrum articulated with frontal margin of carapace Pantomn- 
Genus PANDALUS Leach. 
Pandalus Leach, Edinburgh Encyc., vu, 432, 1814. 
Anterior portion of carapace carinated. First pair of antennae usually not longer than carapace; 
spino on the outer margin of their basal joint obtusely pointed. Outer maxillipeds and first pair of 
legs slender. 
Pandalus longicauda, sp. nov. 
Rostrum twice as long as carapace, nearly horizontal. At the posterior sixth of carapace, a small, 
blunt median spine; in front of this arises the median crest which is unarmed posteriorly, anteriorly 
with about forty small, fixed spines, of which two or three are on the carapace, the remainder on the 
rostrum. Spines larger posteriorly than anteriorly. 
Lower edge of rostrum armed with about thirty 
spines, a little finer and more appressed than the 
superior spines. A perfect ocellus or secondary eye 
is situated on the posterior surface of the ophthal- 
mopod. Antennular flagellum as long as the cara- 
pace and rostrum, in this respect resembling the genus Pandalopsis Bate. Stylocerite oval, subacute. 
Antennal scale as long as carapace. Outer maxillipeds a little longer than antennal scale. Propodal 
and terminal segments subequal. The propodus of the first pair of feet reaches the end of antennal 
scale. Carpus and dactylus subequal; propodus 1.5 times as long as carpus. The feet of second pair 
are subequal and reach the end of antennal scale. Carpus 1.5 times as long as merus and about 
twenty-jointed; proximally the divisions are very faint; distal segment about 3 times the next one, 
which is subequal to each of the four succeeding. Palm a little wider and about as long as adjacent 
carpal segment; fingers of the same length. The carpus of fifth pair of feet overreaches antennal scale; 
propodus 1.5 times as long as carpus; the dactylus very short, less than one-tenth the propodus. Sixth 
abdominal segment much compressed and 3 times the length of fifth; it has a median groove with a 
carina on each side. Seventh segment dorsally grooved; of its three pairs of dorsal aculei, the anterior 
pair is about at the middle of length of segment. 
Male: Length, about 44 mm.; length of carapace and rostrum, 18.5 mm.; length of rostrum 
12.5 mm.; length of flagellum of antennula, 20 mm.; length of sixth abdominal segment, 6.8 mm. 
This species may readily be distinguished by the spine on the posterior part of the carapace. In 
the fixed rostral teeth and long first antenna; it resembles Plesionika Bate; in the ocellus it resembles 
Nothocaris, while the stylocerite is that of Pandalus. 
Mayaguez Harbor, 220 to 225 fathoms, station 6070, 2 specimens. 
The Porto Rican examples being in poor condition, 1 have taken as types two examples collected 
by the Albatross in the Gulf of Mexico, lat. 28° 42' 30" N., long. 85° 29' W., 88 fathoms, station 2403 
I'LL S. Nat. Mus. No. 23568). 
PANTOMUS A. Milne Edwards. 
Pantomus A. Milne Edwards, Recueil de Figures de Orustaees nouveaux ou peu connus, pi. 26, 1883. 
Near Pandalus, but with the rostrum articulated with frontal margin of carapace. According to 
Bate, 1 the rostrum “seems to have the power of movement to a slight extent in any direction at the 
will of the animal; this modification can be due only to one purpose, that of receiving the shock of an 
approaching enemy directly on its point rather than obliquely.” 
Fig. 24 . — Pandalus longicauda, rostrum, x 4. 
1 Challenger Kept., xxiv, p. viii, 1888. 
