THE NAUTILUS. 83 
of the gill. The ova form distinct, subcylindrical placentae. 
The glochidia are subelliptical, nearly semielliptical, about as 
high as long, L. and H. 0.16 mm. They are much like those 
of F. flava, but slightly larger. 
Color of soft parts of the orange type, chiefly evident on the 
foot, mantle-margin, and adductor muscles. However, this 
color is not very intense, often very pale orange, and in young 
specimens the soft parts are sometimes whitish. The gonads 
are red, and so are the eggs and placentae, from pink to bright 
crimson; in some cases they are pinkish-orange. 
This group undoubtedly represents, in the upper Tennessee, 
the flava-group of the interior basin. 
FUSCONAIA EDGARIANA (LEA), F. EDGARIANA ANALOGA (ORTM.). 
(See: F. cor and cor analoga, Oxtmann, 1. ¢., pp. 582-533). 
Most of the specimens preserved in alcohol represent the flat 
headwaters-form (analoga), but I have a sterile female (Ander- 
son Co., Tenn. ), which is the swollen typical form. 
Gravid females: May 13, 14, ’13; July 5, 7, 8, ’138. Of those 
preserved none happened to have glochidia. 
Soft parts identical with those of F. cwneolus, and with those 
of the flava-group in general. Color in most cases deep orange, 
chiefly so foot and adductors. I never found specimens with 
whitish soft parts, and only a few are marked: pale orange. 
Gonads, eggs and placentae rarely pink, mostly intensely 
crimson. 
FuscoNAIA BARNESIANA (LEA) and varieties. (See: 1 c., p. 
534 ff. ). 
The anatomy of this group has been described previously. 
(See: Navutix. 31, ’17, pp. 61, 62.) 
LEXINGTONIA DOLABELLOIDES (LEA), L. DOLABELLOIDES CONRADI 
(VanaTra). (See: 1. c., pp. 545, 546.) 
Gramd females: May 11, 13, 713; July 5, 7, 9, 10, 13, 718. 
Glochidia: May 13 and July 5 (tachytictic). 
All gravid specimens belong to the compressed headwaters- 
form (conradi), but I have examined the soft part of males and 
