THE AMERICAN MIDLAND NATURALIST 51 
Genus XXIX. Lampsiuis (Raf.) 
72. LL. anodontoides (1.ea)—(1. a) 
73. L. fallaciosa (Smith)—(1. a) 
74. L. Higginsit (Lea)—(1. b) 
75. L. Powellit (Lea)—(3. c) 
76. L. luteola (Lamarck)—(3. c) 
(19). L. luteola rosacea (DeKay)—(3. c) 
77. L. reeviana (Lea)—(3. c) 
78. L. ventricosa (Barnes)—(3. c) 
(20). L. ventricosa satura (1ea)—(3. c) 
Genus XXX. TRuNCILLA (Raf.) 
79. T. Curtisi Frierson and Utterback—(3. c) 
80. T. Lefevret Utterback—(3. c) ' 
ENUMERATION OF MISSOURI NAIADES. 
BV AUV ISTORII Seam ar tera & Nok toh sere RE GME ALE TC NS ay CCN eaten Cee ih 2 
SHS DUAN Big 0 OSS ar otis NUN ee Ra eg 2 pent ae gH A Ut cM LSA, Hh, 3 
GONG RAG ar iy octet Eber 2rd URGE LAL ety Dar Hun 30 
SUB G RNIN RAV rice Sie esther ny Madly GR cet ERAN IC Aad RE ate 3 
SRE CUES spre re Reh sito eel ele te eso ett amen aA RVULE ANU A JIT gM a ie 80 
SUP “SEE GRE SH aA ry int ates ier ARRe aE Pe, Per eh UNunve CaN mtLE Luan ier 20 
MOAT LON, OPE CIES HANDS SUB-SRE CLES. 2)! la Salgie sleium eal Orca et heen Ranta naeaets 100 
Explanation of Figures.—For the purpose of illustrating the 
characteristic structures of the animal a few text-figures have 
been inserted immediately under the different Sub-Families. 
All figures illustrating these characters are about life-size and, 
while they are drawn from actual specimens in gravid 
condition, yet the sketches are more or less diagrammatic in order 
to emphasize the essential features. The sketches of the glochidia 
(most of them figured here for the first time) are actual camera- 
lucida drawings by using lenses to magnify 87 diameters. In 
both sets of these inserted figures, as well as in some of the plates 
at the close of the text, the following meanings are given to the 
letters for the labels :— 
A=anal opening; I=inner gill; 
AN=anterior end; M = marsupium; 
AV =—antero-ventral margin; P=palp; 
B=branchial opening; PO =posterior end; 
D=dorsal, or hinge line; S=supra-anal opening; 
F=foot; V=ventral margin. 
Explanation of Terms, Abbreviations, etc., used in the text, 
bibliography and check list.—A few technical terms introduced 
