On Aquatic Carmvorows Coleoptera or Dytiscide. 985 
Fig. 48. Internal laminze of hind cox of Hydroporus diversicornis. 
Fig. 49. Idem %) Hydroporus oblongus. 
Fig. 50. Idem 5 Agabus (Dytiscus brunneus). 
Fig. 51. Idem ss Agabus (Dytiscus bipustulatus). 
Fig. 52. Idem 9 Platambus (Dytiscus maculatus). 
Fig. 53. Idem . A gabinus. 
Fig. 54. Idem ; Copelatus. 
Fig. 55. Idem 55 Agabetes. 
Fig. 56. External lamina and wing of metasternum of Agabus (Dytiscus uliginosus). 
Fig. 57. 35 ‘ 3 Agabus (Dytiscus abbreviatus). 
Fig. 58. 55 oD % Platambus (Dytiscus maculatus). 
Fig. 59. 5 3 " Copelatus. 
Fig. 60. Hind coxa and one side of metasternum of Prodaticus. 
Fig. 61. 55 33 . Hydaticus. 
Fig. 62. es 5 5 Thermonectes. 
Fig. 63. o - v Acilius. 
Fig. 64. Y 5 f Eretes. 
PLATE VIII. 
Fig. 65 Lateral view of articulations at side of breast of Eretes ; a, metathoracic episternum ; 6, meta- 
thoracic epimeron; c, Ist ventral segment; d, hind coxa; ¢, wing of metasternum: in this 
fig. and in fig. 66, the portion on the left of the dotted line is covered by the wing-case in the 
condition of repose. 
Fig. 66, Lateral view of articulations at side of breast of Cybister (Dytiscus reeselii, Fab.) ; lettering as in 
preceding fig. 
Fig. 67. Ventral segments of Dytiscus (D. marginalis.) 
Fig. 68. Idem op Pelobius (Dytiscus tardus.) 
Fig. 69. Dorsal aspect of middle and hind body of Cybister (Dytiscus reeselii, Fab.), with the left wing- 
case and wing removed ; a, vight wing-case ; 6, scutellum; c, mesonotum ; d, point of articu- 
lation of wing-case: e, angle of mesothoracic episternum; /, upper edge of mesothoracic 
epimeron ; g, upper (semicorneous) portion of metathoracic episternum ; /, idem of metatho- 
racic epimeron ; é, line of attachment of wing; /, pieces of metanotum ; /, trochanter of 
articulation between various pieces; m, hind border of metanotum, where is situate the 
metathoracic breathing aperture ; 1 to 8, dorsal plates of hind-body or abdomen ; 1* to 6%, 
upper edges of ventral plates of hind-body ; s' to s, abdominal stigmata or breathing 
apertures. 
Fig. 70. Superior oblique lateral view of right side of hind-body, and metasterno-coxal articulation of 
Dytiscus latissimus ; @, portions of metanotum ; 0, metathovacic epimeron ; c, angle of hind- 
coxa; d, metathoracic stigma; ¢, side piece of first ventral segment; f, stigmatic ruge ; 
g, first abdominal stigma; 1 to 8, dorsal plates of hind-body: this diagram is made from a 
specimen distended by stuffing with cotton-wool, so that the membranous portions are shown 
as fully as the corneous. 
. 7]. Outline of front foot of Hyphydrus ¢, (Dytiscus ovatus, L.) 
ig. 72 
» U8) 
. Outline of front foot of Hydroporus ¢. 
. Outline of front foot of Necterosoma. 
. 74, Anterior tibia and tarsus of Noterus ¢ (after Schiddte, Dan. El. XVIII, &). 
