ORTMANN: FAMILIES AND GENERA OF NAJADES. 253 
Quadrula mortoni (Conrad). 
Three males and two females, one of the latter gravid, from Bayou 
Pierre, De Soto Parish, Louisiana, collected by L. S. Frierson, Aug. 6, 
1910. 
Agreeing in every detail with pustulosa and spherica, to which it is 
allied. The inner edge of the anal opening is almost smooth. 
In the gravid female, eggs and glochidia were present, the latter 
of the usual shape, of medium size, subovate, without hooks. The 
glochidia are quite young and their shape is not very distinctly seen. 
They were of whitish color, and distributed in an irregular way in 
certain ovisacs both of the outer and inner gills, many ovisacs being 
empty. No exact measurements of the glochidia can be given. 
The date for the breeding season should be noted. 
Quadrula lachrymosa (Lea). 
One male and four females from the Wakarusa River, Lawrence, 
Douglas Co., Kansas, received from R. L. Moodie, and one female 
collected by myself in the Ohio River, at St. Marys, Pleasants Co., 
West Virginia. No gravid females have been seen. 
Soft parts described by Simpson (cf. Baker, 1898, p. 84). 
Similar to the preceding species. Inner edge of the anal opening 
irregularly and indistinctly crenulated, almost smooth. Posterior 
margins of palpi connected for over one-half, almost two-thirds, of 
their length. 
All four gills are marsupial, septa of the inner ones slightly less 
crowded than those of the outer ones (see Plate XVIII, fig. 1). 
Soft parts whitish. 
Quadrula aspera (Lea). 
Three males, one female (all small, or of medium size) from Bayou 
Pierre, De Soto Parish, Louisiana, collected by L. S. Frierson, and one 
very large female from Pearl River, Jackson, Hinds Co., Mississippi, 
collected by A. A. Hinkley. 
An incomplete description is given by Lea (Obs., X, 1863, p. 
437). 
Agreeing in every respect with Q. lachrymosa, to which it is closely 
allied. Even the minor details (anal opening, palpi, etc.) are abso- 
lutely identical. No gravid females have been seen. 
