THE MAk^lTH M OF THE UXIOXID/E. 



GEORGE LEFEVRE AXD \VINTERTON C. CURTIS. 



In a reo-nt preliminary announcement of a new -y-tern of 

 < l.i ifiration <.|" the I 'nionida- which is based upon a -tudy of the 

 anatomy of the fre-h-water mu els of Pennsylvania, nrtinann 1 

 suggest^ a divi-ii.n !" the tainii\ exclusive of the Hyriina-i into 

 four subfamilies, nameK. Margaritaninae, Unioninae, Anodontina- 



and I.amp-ilii'.e. re-pect i\ ely. Hi- arrangement lav- especial 

 enipha-i- fii tin- ilia: of tin- marsupiuiu and involves 



several important modifications of Simpson's classification, whirh 

 In m.iintain- nni-t be recast to a I "ii-iderable extent in ordi i 

 make it repre-ent tin- nalural attmitie- .f the group. Although 

 it will not In- pn--ible in fiiMn an opinimi in regard to tin- validity 

 it ihc priipo-cd change- before tin- appearance of his detailed 

 results, lie h. - undoubted I \ I alien intu a M-riotis error \\ i h res] 

 in ihe iiiar-upiinn "I "lie it lii- >ul itamilies, and it is the object 

 "1 ilie present imie tn |i<iint out tin- mi-take. 



In i -I i net i imi \\ iih tin- tie-li- \\aier m n --i I in\ e-ti-ations \\ hit h 

 ha\ e been u l)< lei u a V in tlli- la 1 ii ua 1 1 'I ime time and whieh 



ha\e bi-en t amid ..n |..r the I nited ^lates Bureau of Fi^hei 

 I'limaiih Im" the purpn-e "I deifrminin- the feasibility' of arti- 

 ficial pnipa.uaiiiin of the I nimiid.!-. we have had occasion io 

 give attention to the anatomical and histological structure of the 

 marsupium in a lar^e number "I ^i nera, and, furthermore, \\ e 

 ha\e been paitit ulaib in d \\ith the change- that oeeur in 



the gills during the pt rind ! -^ia\ itlity. Since a fundamental di 

 i re|'.un > e\i-i- between < >itinann'- de-rri|>tion of the gravid i;ill 

 in hi- -ublamiK Am tlmnina' antl our o\\ n observations on at lea-t 

 three ul the i^eiieia \\liith lie include- in thi- ^r<Mi]i. nameK', 

 Alasmidonta, Anodmita and >\ inphynota, we ha\i- thought it 

 ad\ i-able t" call attention t.. the tact. 



Ortmann tp. 117 makes the following rather a-toni-hing state- 

 ment concerning the -tnicture "I the marsupium of the Anodon- 



'.\ \r\\ >\ -t.-in 1.1 tin- t Fnionidse," A. V.. ' 'rtmann. Xantilus, XXIII, February, 

 1910, pp. 1 14-120. 



