54 University of Michigan 
Paraptera fragilis (Raf.) =U. gracilis Bar., Ortmann, 18, p. 572. 
Lamp. gracilis (Bar.) =U. fragilis Raf., ’20=Lasmonos fragilis 
Raf., °31; Walker, ‘18¢, p. 182 (“if identifiable”). 
The description of U. fragilis, chiefly its comparison with 
U. leptodon, makes it sure that this is the gracilis Bar. The 
shell is thin, fragile, not elongate and attenuated posteriorly 
(as leptodon is), but somewhat dilated behind. Also the char- 
acters of the pseudocardinals are mentioned. 
It remains doubtful whether Lasmonos fragilis is this shell 
or Leptodea leptodon (see under the latter). 
Genus CARUNCULINA Simpson, 1898 
Type: Unio parvus Barnes. 
Toxolasma Rafinesque, °31, p. 2 (no type named). 
Corunculina Simpson, ’98, p. 109 (error typographicus) (only spe- 
cies, U. parvus Bar.). 
Carunculina Simpson, ‘co’, p. 563, and ’14. p. 148 (type, Unio tex- 
asensis Lea). 
Toxolasma Raf., Frierson, ’14*, p. 7 (type, lividus Raf. =glans 
Lea); Ortmann, 718, -p. 572: 
The revival of the generic name To.volasma depends upon 
the identity of U. lividus Raf. As will be shown under Car. 
mosta, lividus is not recognizable, and thus the name T0.ro- 
lasma should be discarded. 
As type of Carunculina, U. parvus must be taken, for at the 
first publication of this subgenus only this species was included. 
CARUNCULINA MasTA (Lea), 1841 
Type locality: French Broad River, East Tennessee. 
Unio (Toxolasma) lividus Rafinesque, ’31, p. 2. 
Unio pullus Conrad, ’38,.p. 100, pl. 55, f. 2. 
Unio mastus Lea, 41, p. 82. 
Unio cylindrellus Lea, ’68, p. 144. 
Unio corvunculus Lea, ‘68, p. 144. 
Unio glans Pilsbry and Rhoads, ’96, p. 502 (not glans Lea, ’34). 
Lampsilis cylindrella (Lea), L. masta (Lea), L. corvunculus (Lea), 
L. pullus (Con.), Simpson, ’14, pp. 155-160. 
