REPORT ON PORTO RICAN ISOPODA. 
By H. F. MOORE. 
The Isopoda collected in Porto Rico by the Fish Hawk during January and 
February, 1899, include but seventeen species, but the collection is interesting in 
furnishing two new genera, one of considerable interest, and eight species apparently 
not before described. In all, eleven families and fifteen genera are represented. They 
are as follows: 
Tribes. 
Families. 
Genera and species. 
Chelifera 
Apseudidae 
Apseudes espinosus, n. sp. 
Tanaidte 
Leptoehelia incerta, n. sp. 
Flabellifera 
Cirolana mayana Ives. 
parva Hansen, 
obtruncata Richardson. 
Branchuropus littoralis, n. gen. and sp. 
CorallanidEe 
Corallana tricornis Hansen. 
Alcironidae 
Alcirona hirsute, n. sp. 
Nalicora rapax, n.gen. and sp. 
iEgidee 
HDga ecarinata Richardson. 
Rocinela signata Schiodte & Meinert. 
Cymothoidfie 
Anilocra laticauda Milne-Edwards. 
Sphseromidae 
Cilicea eaudata Ives. 
Dynamene perforata, n. sp. 
Cleantis planieauda Benedict. 
Ligia gracilis, n. sp. 
Oniscoidea 
Ligiidae 
Oniscidie 
Philoscia culebrse, n. sp. 
All of these are littoral or shoal-waters species, none of them being taken in water 
deeper than 75 fathoms. 
Key to. tribes and families of Porto Rican Isopoda.* 
a. Head united with first segment of thorax; first pair of thoracic limbs chelate: pleopods not branchial, 
sometimes absent Tribe Chelikera 
b. First antennae biflagellate; second antennae with multiarticulate flagellum Apseudidie 
bb. First antennae uniflagellate (flagellum obsolescent in female); second antennae without scale, flagellum 
small T ANAIDAS 
aa. Head and first thoracic segments not united; first pair of thoracic limbs not chelate; pleopods, all, or some, 
branchial. 
*Key in part from Stebbing after Hansen. 
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