NAIADES OF MISSOURI 119 
Warsaw specimen. ‘They are rotund, inflated, epidermis greenish 
and approach the spherical form of the juvenile peruviana. Beaks, 
even in these young shells, are too eroded to make out the sculp- 
tural markings. 
MISCELLANEOUS REMARKS:—Since Amb. perplicata is a 
Southern species it is only found in this state in typical form in 
the south drainage of the Ozark Uplift. Personal collections 
made by the writer from the St. Francis are found to compare 
well with typical perplicata shells received from Mr. Frierson and 
taken from type localities. This species is also sparingly found 
in the Osage where its subspecies, quintardi of Cragin is the pre- 
dominant form of Amblemae, and from which it is distinguished 
by the smaller, more compressed, and much plicated shell of 
the latter. Under the description of Amb. rartplicata the dis- 
tinguishing features between that species and perplicata have 
been mentioned. At first the inclination was to set this species 
down in the synonomy of rartplicata from general shell features, 
but the few specific differences in shell as well as that of geo- 
graphic range are enough to make it distinct. This species is 
tachytictic, being found gravid by Wilson and Clark (1914, p. 42) 
from May until July inclusive. The writer examined many through- 
out June and July to find none gravid; however, its subspecies 
(quintardi) was found gravid during’ these months and because 
of these fact some reason was given that this smaller, compressed 
form was only the female of the larger one, just as seen in case of 
Plagiola securis or Obovaria retusa. 
Amblema perplicata quintardi (Cragin) 
(‘Little Blue-Point,”’ ‘‘ Multiplicate.’’) 
Pl. XVIs Figs: 38 A—D. 
1887— Unio quintardii Cragin, Bull. Wahb. Coll., II, p. 6; Pilsbry, 
Pr. Ac. N. Sci. Phila:, 1892, p. 131, pl. VII, figs, 1-3. 
1891— Unio pilsbryt Marsh, Nautilus, V. pp. 1 and 2; Nautilus, VII, 
1893, pl. I, figs. 7 and 8. 
ANIMAL CHARACTERS. 
NUTRITIVE CHARACTERS:—Similar to those of the species, 
having its anal and supra-anal openings often unconnected by 
mantle edges, free laminar edges of inner gills, palpi mostly con- 
nected by their edges, and being colored a dirty white or tan; 
reproductive structures also rather identical in possessing marsupia 
