Illustration from Diatomaceae of Philadelphia and Vicinity. Original description follows:
<p><br></p><p>PLATE 31
</p>
<table><tbody><tr><td style="vertical-align:top;">Fig.</td>
</tr><tr><td style="vertical-align:top;">1</td>
<td style="vertical-align:top;">Navicula elegans Wm. Sm.</td>
</tr><tr><td style="vertical-align:top;">2</td>
<td style="vertical-align:top;">Navicula elegans var. cuspidata Cl.</td>
</tr><tr><td style="vertical-align:top;">3-4</td>
<td style="vertical-align:top;">Navicula grevillei (Ag.) Cl.</td>
</tr><tr><td style="vertical-align:top;">5</td>
<td style="vertical-align:top;">Navicula libellus Greg.</td>
</tr><tr><td style="vertical-align:top;">6-7</td>
<td style="vertical-align:top;">Navicula palpebralis Bréb.</td>
</tr><tr><td style="vertical-align:top;">8</td>
<td style="vertical-align:top;">Navicula rhyncocephala Kuetz.</td>
</tr><tr><td style="vertical-align:top;">9</td>
<td style="vertical-align:top;">Navicula cryptocephala Kuetz.</td>
</tr><tr><td style="vertical-align:top;">10</td>
<td style="vertical-align:top;">Navicula longa (Greg.) Ralfs.</td>
</tr><tr><td style="vertical-align:top;">11</td>
<td style="vertical-align:top;">Pinnularia brébissonii (Kuetz.) Cl.</td>
</tr><tr><td style="vertical-align:top;">12</td>
<td style="vertical-align:top;">Pinnularia borealis Ehr.</td>
</tr><tr><td style="vertical-align:top;">13</td>
<td style="vertical-align:top;">Pinnularia divergens var. elliptica Grun.</td>
</tr><tr><td style="vertical-align:top;">14</td>
<td style="vertical-align:top;">Epithemia turgida (Ehr.) Kuetz.</td>
</tr><tr><td style="vertical-align:top;">15-21</td>
<td style="vertical-align:top;">Epithemia argus Kuetz.</td>
</tr><tr><td style="vertical-align:top;">16</td>
<td style="vertical-align:top;">Epithemia argus var.?</td>
</tr><tr><td style="vertical-align:top;">17</td>
<td style="vertical-align:top;">Epithemia muelleri A. S.</td>
</tr><tr><td style="vertical-align:top;">18</td>
<td style="vertical-align:top;">Epithemia zebra var. proboscidea (Kuetz.) Grun.</td>
</tr><tr><td style="vertical-align:top;">19</td>
<td style="vertical-align:top;">Epithemia gibberula var. producta Grun.</td>
</tr><tr><td style="vertical-align:top;">20</td>
<td style="vertical-align:top;">Epithemia musculus Kuetz.</td>
</tr><tr><td style="vertical-align:top;">22</td>
<td style="vertical-align:top;">Epithemia musculus var. constricta (Bréb.) V. H.</td>
</tr><tr><td style="vertical-align:top;">23</td>
<td style="vertical-align:top;">Rhopalodia gibba (Kuetz.) Mueller</td>
</tr><tr><td style="vertical-align:top;">24</td>
<td style="vertical-align:top;">Rhopalodia ventricosa (Kuetz.) Mueller</td>
</tr></tbody></table>
Charles Sumner Boyer (1856-1928).
1916
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