y N I 



Spocies ^'07. iMus. Ciiniing in Brit.) 



UxiO MARGINATUS. Uii. /t-du ublongci, siilicuiieifuniii, 

 cnissd, lifvigald, subluted, fasciis slriykque iiiterrup- 

 iis viridibm radiata, intiis albidd, denfibiis cardmalibus 

 in iitrdqiie valvuld und, shnplicibiis, dentibiis laterali- 

 bus iiallis ; latere poslico oblongo, valde angidulo, 

 post, augnlum complanato, super angnlnm siibiiodoso, 

 ante angulttm concavo, margine dorsali dectivi, war- 

 gine ventrali medio convexo, mnbonibiis poslice angula- 

 tini elevatis ; latere antico irevinsciilo, margine veil- 

 trnli rotundatim acclivi, margine dorsali depresso. 



The bordeked Unio. Shell oblong, subciineiforiii, 

 thick, smooth, yeHo^^ish, rayed with interrupted 

 green bands and stripes, whitish within, cardinal 

 teeth one in each valve, simple, no lateral teeth; 

 posterior side oblong, strongly angidfir, flattened l)c- 

 hind the angle, nodulose upon the angle, concave in 

 front of the angle, dorsal margin sloping, ventral 

 margin convex in tiie centre, with the uuiboes poste- 

 riorly angularly elevated ; anterior side rather short, 

 ventral margin roundly sloping up\var<ls, dorsal mar- 

 gin (le))ressed. 



Lea, American Philosophical Transactions. 

 Unio varicosns, Lam. 

 irga rugulosa, Wood. 



Hab. Massachusetts. 



The space behind 

 obliquely truncated. 



and as it we 



Species 268. (Mus. Cuming in Brit.) 

 T^NIO PaRANENSIS. Un. testa roliindd, crassd, snbcom- 

 pressd, olivaceo-castaned, trerigatd, coneenlriri rugatd, 

 intiis n/bii, deiiiihiis (■(irdiiialiljns iino et duobns, irregii- 

 lariter xcrnilix, dmldina UitrniUhm laminatis, umljoni- 

 bus lateralili-r ti:riiinuiHhns, margine dorsali elevato, 

 roiii'i'xo, area impressd et angulo radiato. 

 The Para Unio. Shell round, thick, rather compressed, 

 olive-chestnut, smooth, concentrically wrinkled, white 

 within, cardinal teeth one and two, irregularly ser- 

 rated, lateral teeth laminar, nmboes laterally terminal, 

 dorsal margin elevated, convex, rayed with an im- 

 pressed area and angle. 

 Lea, Trans. Am. Phd. Soc. ,'5. t. U. f. -l;.'. 



Unio Solsiana, D'Orbigny. 

 Ilab. River Parana. 



Of a singularly rounded foi-ni, with the umboes late- 

 rally terminal. 



Species 2G9. (Mus. Cuming in Brii.) 



Unio Von Buschea. Un. testa inaqnaliter otali, tenni, 

 lavigatd, olimceo-ca-daned, siibaured, snbinfatd, intiis 

 alba, epiderinide postice rngatd ; latere postico latu, 

 oblongo, obliqne iriang/dato, lermino oblique, trnncato, 

 margine dorsali recto, elevato, margino ventrali con- 

 vexo, prope angulmn snrsiim. acclivi; latere antico 

 brcvis-iimo, margine dorsali bred, redo, teriniiio an- 

 gnlato, termine laterali rolniido, dcntibns cardinaiibns 

 in nirdqne vakd nno, denlibns lateralibus nidlis. 



Von Busche's Unio. Shell unequally oval, thin, smooth, 

 olive-chestnut, golden-tinted, somewhat inflated, 

 white within, epidermis posteriorly wrinkled ; pos- 

 terior side wide, oblong, with three oblique angles, 

 end obliquely truncated, dorsal margin straight, ele- 

 vated, ventral margin convex, sloping upwards near 

 the angle ; anterior side very short, dorsal margin 

 short, straight, with terminal angle, lateral tcnniua- 

 tiou rounded, cardinal teeth one in ciicli valve, uo 

 lateral teeth. 



Lea, ? MS. Cuming's Cabinet. 



llah. ? 



Species 370. (Mus. Cuming in Brit.) 



I'NtO PoulsoNI. Un. testa .fiibovali, alatd, snblfpdgatu, 

 castaneu-nigrescenli, siibinflatd, intiis purpurea ; latere 

 postico lato, oblongo, perobliqtte angnlis duobns eleva- 

 tis radiata, lermino infra angulos proditdu, rulunda- 

 lo, margine dorsali in alam elecato. lunrgiue n-nlntli 

 poslice concexo, medio vix contrado : latere anliro 

 brevi, angustalo, tenniui) rotunda, dculibiis rnrdinali- 

 hus uuo et duobus, di-nlibus laleridibwi himiuatis. 



Poulson's Unio. Shell somewhat oval, alated, rather 

 smooth, blackish-chestnut, rather inflated, purple 

 within ; posterior side wide, oblong, very obliquely 

 rayed with two elevated angles, the end produced 

 and rounded beneath the angles, dorsal margin raised 

 into an angle, ventral margin posteriorly convex, 

 very slightly contracted in the middle ; anterior side 

 short, nari'ow, i-ounded at the end, cardinal teeth one 

 and two, lateral teeth laminar. 



Con HAD, Freshwater Siiells. 



Uiiio pnrpuratus, Lamarck. 

 Unio aler. Lea. 

 Uuio lugubris. Say. 



Ilab. JMississippi. 



This is the most oval of the alate species in general 



form, and has the li'ast prominent dorsal wing of any. 



November, 1SG6. 



