268 BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



Family X. LIMNORIID.^.« 



Body oblong, .subdeprossed, contractile into a ball. Head short 

 and blunt in front. Both pairs of antennae small, subequal; flag-ella 

 short. Mouth parts normal. Mandibles without molar expansion; 

 with a small, three-jointed palp. Palp of maxillipeds composed of five 

 articles. Eyes lateral. 



Segments of thorax distinct; first segment longer than second. 

 Epimera well defined on all the segments of the thorax with the excep- 

 tion of the first. 



Abdornen composed of six distinct segments; terminal segment 

 large, broad, flattened above. 



Legs all ambulatory. 



Pleopods uniform in structure, both natatory and branchial; inner 

 pkite of second pair in male with a stylet. 



Uropoda small, lateral; outer branch short, unguiform, almost obso- 

 lete; inner l)ranch linear. 



44. Genus LIMNORIA Leach. 



Only genus. With characters of family. 



parium quinque priorum per paria sensim longitudine et robore crescentes, paris 

 sexti et septimi prfecedentibus paulo breviores atque tenuiores, minus curv^atte. 

 Carina pedum parium quattuor posteriorum evanida. 



Cauda profunde immersa, lateri))us annulorum trium priorum, saltern alterius 

 lateris, obtectis, annuli secundi, tertii, (|uarti, quiuti coujuuctim leviter curvatis, vix 

 convergentibus: convexiuscula, paulo vel vix latior quam lougior, quam truncus 

 cum capite plus duplo brevior. Annulus primus magnam vel uiaximam partem 

 obtectus; annulus secuudus, tertius, quartus longitudine subtequales, quam annulus 

 quintus fere sesqui breviores. Margo posticus annulorum quattuor priorum latissime 

 sinuatus; annuli quinti subrectus, obscure flexuosus. Anguli postici annuli secundi, 

 tertii, quarti, quinti prorainuli, integri, breviter rotundati. Annulus analis breviter 

 subtriangulus, quam annulus quintus caudalis paulo angustior, sesqui ferme latior 

 quam lougior (fere 5:7), annulis ceteris caudalibus conjunctis sesqui longior. Pedes 

 auales quam annulus analis paulo longiores; ramus interior quam exterior fere sesqui 

 brevior et paulo angustior, producte laminatus; ramus exterior subfalcatus, acutius- 

 culus, leviter tiexuosus. Long. 8-18 mm. 



Color cereus, maculis majoribus vel minoribus, fuscis, racemosis, in series trans- 

 versas digestis, in medio corpore sparsus; oculi nigri. — Schicedte and Meinert, Nat. 

 Nat. Tidsskr. (3), XIV, 1883-84, pj). 390-395. 



For description of the male and the young of the second stage, see same reference, 

 pp. 392-395. 



« See Hars for c-haracters of family. Crust, of Norway, II, 1899, j)]). 74-75. 



