No. 26.] ARTHROSTRACA OF CONNECTICUT. I9I 



CYMOTHOIDEA Or FLABELLIFERA. ASELLOIDEA Or ASELLOTA. 



Anthuridse. Asellidae. 



Cyathura carinata (Kr6yer). fAselliis communis Say. 

 Ptilanthura tenuis Harger. Janiridse. 



Cirolanidas. Jcera marina (Fabricius). 

 Cirolana concharum (Stimpson). bopyroidea or epicaridea. 



^gidse. Bopyridje. 



^ga psora (Linn). *Stegopkryxus hyptius Thompson. 



Cymothoidae. *Probopyrus pandalicola (Packard). 

 Mgathoa oculaia (Say). - oniscoidea. 



Livoneca ovalis (Say). _ Oniscidse. 



Limnoriidte. XOniscus asellus Linn. 



Limnoria lignorum (Rathke). Pliiloscia vittata Say. 



Sphaeromidae. XCylisticus convexus (DeGeer). 



Sphceroma quadridentatum Say. XPorcellio rathkei Brandt. 



IDOTHEOIDEA or VALVIFERA. JF. spinicomis Say. 



Idotheidae. tP. scaber Latreille. 



Chiridotea cwca (Say). XMetoponorthus pruinosus (Brandt). 



C. tuftsii (Stimpson). Actoniscus ellipticus Harger. 

 *Idothea metallica Bosc. Armadillididse. 



/. baltica (Pallas). XArmadillidium vulgare (Latreille). 

 /. phosphorea Harger. Scyphacidas. 



*Scyphacella arenicola Smith. 



KEY TO THE GENERA OF I SO POD A. 

 A. First pair of legs chelate, uropods terminal. 



B. Uropods simple, short, uniramous, pleopods three pairs 



Tanais p. 193 



BB. Uropods biramous, pleopods five pairs Leptochelia p. 195 



AA. First pair of legs not chelate. 

 B. Uropods lateral. 



C. Outer ramus of uropods arching over base of telson. 



D. Maxillipeds with uniarticulate palp Ptilanthura p. 200 



DD. Maxillipeds with biarticulate palp Cyathura p. 198 



CC. Outer ramus of uropods not arching over base of tel- 

 son, and uropods not inflexed ventrally. 

 D. Abdomen of six segments. 



E. Uropods with one ramus rudimentary ...Limnoria p. 211 

 EE. Uropods with both rami well developed. 



F. Maxillipeds with palp free and margins of last two 



joints never furnished with hooks ...Cirolana p. 203 

 FF. Maxillipeds with palp embracing distal portion of 

 buccal mass. 

 G. Both pairs of antennae with peduncle and flagellum 



well defined iEga p. 205 



GG. Antennas much reduced, without clear distinction 

 between peduncle and flagellum. 

 H. Head produced posteriorly in three lobes, a 

 larger median one and two small lateral 



ones .ffigathoa p. 207 



HH. Head not produced posteriorly. .Livoneca p. 209 



DD. Abdomen of two segments Sphaeroma p. 212 



CCC. Uropods inflexed ventrally and valve-like. 



