THE NAUTILUS. Vll 



Unionidee, African forms . . . 107 



Unionidae, Asiatic forms . 106 



Unionidae, North American forms . . . 104 



Unionidae of Pearl and Sabine Rivers . . .134 



Unionidae, South American forms . . 108 



Unionidae, notes on oriental . . . 92, 97 



Unionidae, The discharge of the glochidia. . , .94 



Whitfield, Professor Robert Parr . . . . .11 



Zonitoides milium from the District of Columbia 24 



