STATION IN FRESH-WATER MUSSELS. 297 
Unio coccineus Lea, ’38 (Ohio R., Marietta; Mahoning R., Ohio; 
Columbus, Ohio). 
Dia.: 53 per cent. 
Unio fulgidus Lea, ’45 (Alexandria, La., probably a mistake). 
Dia.: 60 per cent. 
2. PLEUROBEMA CORDATUM COCCINEUM (Conrad).—Dia. less 
than 50 per cent. 
Unio coccineus Conrad, ’36 (Mahoning R., near Pittsburgh).— 
Quadrula coccinea Simpson, ’14, p. 883. 
Dia. (Conrad) : 37 per cent.; (Simpson) : 43, 46 per cent. 
Loc. No. Max. Min. Av. 
Ohio River. 
IDorPseMOVbid Mad sanemodasanee ces ee 2 67 56 61.5 cat. 
Portal ie tot vers miererecyorsycuieteasteteiets ane B 64 55 60 cat, 
S tA Milaiiaye Sis oe re teeny oer: ek tee 4 67 50 63 cat. 
MORON OMe eee were esate 6 62 54 58 cat. 
GookssMet ny ote iueecs ceireiie saree 14 65 50 57 cat. 
endasttiyinysiant scene sion ae comin skies 16 64 52 57 cat. 
(Cora poliswersacmast teeter ree osien I 51 51 51 cat, 
Allegheny River. 
INAtROTaA sera ct hore cs evar ciatere teres I 56 56 56 cat. 
AN EXGKGbin Ripon cera e Boe eaeeeeure ae 5 56 53 54 cat. 
Goclineig wpa tec teie pyar esboer 22 63 4I 54 cat. (cocc.) 
AOMMettammm nyse ie caiieisiciela aie a hes oaks I 55 55 55 cat. 
Kelvans BMA COCO CAT eae 67 62 40 51 cat. (cocc.) 
diempletone vod athacccteveveovoecke sons 2 53 49 SI cat. (cocc.) 
Weubotshe IsyonGl 3b nenoceaceaueeoase I 56 56 56 cat. 
PbO Mes bate reper ary e set ers egatenee Keeeivenars I 47 47 47 coce. 
EA CKO Type a tse ee 3 54 45 49 cocc. (cat.) 
A iciretve times nies srt eS erans sicrsacns eeoreteme tas 2 54 49 BES. cata (eoccs) 
eA Cer easy striate sic oe elektro 12 ist 44 47 cocc. (cat.) 
Thus catillus does not entirely disappear in the headwaters of the 
Allegheny River. This is different in French Creek, which goes 
into the Allegheny above the station of Templeton in the last table, 
where the average diameter is 51 per cent. 
Loc. No. Max. Min. Av. 
French Creek (follows Templetion). 
WIIG, “aaa aclonaabaie Goee eee 3 52 35 43 cocc. (cat.) 
Cambridge: Springs) seas. tesa 6 45 37 42 coc. 
Conneauttee Creek, Edinboro .... I 4I 41 41 coce. 
Leboeuf Creek, Waterford ...... 2 43 38 40 coce. 
