XII LIST OF ILLUSTRATIONS. 



Page. 



Ischnura cervula. 94. Male, segment. 95. Male, segment dissected. 96. 

 Male, segments, ventral view. 97. Male appendages. 98. Male prothorax. 

 99. Female prothorax. 100. Female mesostigmal lamina. Ischnura pcrparva. 

 101. Male, segment. 102. Male, segments, ventral view. 103. Male pro- 

 thorax. 104. Male appendages. 105. Female mesostigmal lamina 303 



Ischnura cervula. 106. Teneral female with light coloration. 107. Teneral 

 female with dark coloration. 108. Female with very dark coloration wliich 

 approaches male coloration. 109. Male coloration 304 



Ischnura perparva, female. 110-114. Variations in teneral coloration. 115. 

 Stage intermediate between teneral and adult, showing formation of adult 

 coloration on segments. 116. Adult coloration. Ischnura cervula, female. 

 117. Teneral female with light coloration. 118. Teneral female with dark 

 coloration showing formation of adult coloration on eyes and femora. 119. 

 Female, final or senile coloration 305 



120-121. Ischnura cervula, nyvo-Yih.. 122. Ischnura perparva, UYva^h. 306 



Ischnura perparva, nymph. 123. Dorsal view of labium. 124-126. Mental 

 seta of three reared nymphs. Ischnura cervula, nymph. 127. Dorsal view of 

 labium. 128-130. Mental seta of three reared nymphs. 131. Male seg- 

 ment, ventral \\qw. 132. Female segment, ventral view 307 



MacTomia magnifica, male. 133. Dorsal view. 134. Lateral view 314 



Macromia magnifica, female. 135. Dorsal view. 136. Lateral view 316 



Macromia magnifica. 137-138. Segment of male. 139-141. Segment and 

 appendages of male. 142-144. Segments of female. 145. Front leg of male 

 showing tibial keel 317 



Macromia magnifica, nymph. 146. Dorsal view. 147. Lateral view with 

 labium extended 318 



Macromia magnifica, nymph. 148. Labiiun. 149. Abdomen. 150. Segments 

 of abdomen, ventral view. 151. "Face." 152. Lateral view of head. 153. 

 Antenna. Macromia illinoiensis, nymph. 154. Labiima. 155. Abdomen. 

 156. Segments of abdomen, ventral view. 157. Lateral view of head. 158. 

 Antenna 319 



Macromia magnifica, copulation (159) 320 



Agrion aequabile yakima. 160-161. Wings of male and female showing extent 

 of color. 162. Segment of male. 163. Penis. 164. Male appendages. 165- 

 166. NjTnph. 167. Dorsal Adew of labium of nymph 323 



Lestes congener, nymph. 168. Lateral view. 169. Dorsal view. 170. Lab- 

 ium. 171. Head, lateral view. 172. Segments 324 



Lestes uncatus, nymph. 173. Lateral view. 174. Dorsal view. 175. Labiimi. 



176. Head 325 



Coenagrion resolutum. Yll. Male appendages. 178. Segment and penis. 179. 

 Male prothorax. 180. Female prothorax showing the right dorsal "pit." 

 181. Mesostigmal lamina. 182-183. Male color patterns. 184. Female 

 color pattern 326 



Coenagrion resolutum, nymph. 185. Lateral view. 186. Dorsal Adew. 187, 

 Detail of caudal gill. 188. Lateral fold of abdomen showing the spinulose 

 edge. 189. Labium 327 



Ophiogomphus severus, nymph. 190. Lateral view. 191. Dorsal view. 192. 

 Segment. 193-194. Labium. Ophiogomphus occidentis, nymph. 195. Ab- 

 domen, dorsal view. 196. Segment. 197. Labium. Gomphus sp. 198. 

 Dorsal view. 199. Head. 200. Labium. 201. Segments 328 



Dermal plates of Stegosaurus stenops Marsh 356 



Diaptomus virginiensis. Lateral wing last cephalothoracic segment 457 



Diaptomus virginiensis. Abdomen of female 457 



