NATURAL SCIENCES OF PHILADELPHIA. 169 



Prodromus descriptionis animalium evertebratorum, quae in Expeditione ad 

 Oceanuni Pacificum Septentrionalem, a Republica Federata missa, Cadwala- 

 daro Binggold et Johanne Bodgers Ducibus, observavit et descripsit 

 W. STIMPSON. 

 Pars. 1 1. TURBELLARIEORUM NEMEETINEORUM 



GENERUM ET SPECIERUM ADHUC INEDITARUM DESCRIPTIONES ; 

 ADJONCTIS NOTIS DE GENERIBUS JASI CONSTITUTIS. 



Characteres, ex quibus generura distinctiones pendent in hoc tribu, sunt ; 

 corporis forma, longissima v. brevior et lata, plana v. teretiuscula ; forma capi- 

 tis discreti t. continui ; positio proboscidis aperturse, (os, Quatrcf.,) terminalis 

 V. subterminalis ; et prassentia aut absentia aperturje ventralis, (os, Grube ; aper- 

 tura genitalis, Qualrcf.) lobarum, plicarum frontalium, fissurarum lateralium, 

 efrocellorum. Aperturam parvulam (anum v. ap. genitalem) apud extremitatem 

 corporis posteriorem describunt auctores, quam uunquam invenire potui in 

 speciebus quas observavi. 



Genera adhuc proposita sunt : 



LiNEUS, Sowerby, 1804. 



Tdbulanus, Renier, 1807. 



Cerebratclos, Renier, 1807. 



JVemeries, Cuvier, 1817. = Lineus, 



Eorlasia, Oken, 1817. = Lineus. 



LoBiLABRUM, Blalnville, 182-. 



Folia, Delle Chiaje, 1823. Prseoc. — Folia, Ochsenheim, Ins. 1816. 



Ophiocephalus, Delle Chiaje, 1823. 



Meckelia, Leuckart, 1828. = Cerebratulus. 



Notospermus, Huschke, 1830. 



MiCRDRA, Hemprich et Ehrenb., 1831. 



Tetrastemma, Hemp, et Ehrenb., 1831. 



Ojiatoplea, Hemp, et Ehrenb., 1831. 



Hemicyclla., Hemp, et Ehrenb., 1831. 



Polystemma, Hemp, et Ehrenb., 1831. 



Amphiporus, Hemp, et Ehrenb., 1831. 



Notogymnus, Hemp, et Ehrenb., 1831. = Notospermus. 



Tricelis, Hemp, et Ehrenb., 1831. = Notospermus. 



Carinella, Johnston, 1833 ; fide ejusd. = Meckelia. (Cereeratulus.) 



Aerostomum, Grube, 1840. (v. Acrostoma, Le Sauv., Verm., 1826.) 



Rhamphogordius, Rathke, 1843. 



Cephalotrix, Oersted, 1844. 



Borlasia, Oersted, 1844. 



Nemertes, Oersted, 1844. 



Amiihiporus, Oersted, 1844. (non Ehrenb.) 



Astemma, Oersted, 1844. 



Serpentaria, Goodsir, 1845. 



Valencinia, Quatref., 1846. 



Oerstedia, Quatref., 1846. 



Scotia, R. Leuckart, 1849. 



Baseodiscus, Diesing, 1850. 



Colpocephalus, Diesing., 1850. 



Chlamydocephalus, Diesing, 1850. 



Prorynchus, Schultze, 1851. 



Emea, Leidy, 1851. 



Hecate, Girard, 1852. 



Poseidon, Girard, 1852. 



Nareda, Girard, 1853. 



Renieria, Girard, 1853. 



Leodes, Girard, 1853. = Cerebratulus. 



1857.] 



