EXPLANATION OF THE PLATES. 



Plate l.—See Art. XXXV. 30 and 32. 

 Fig. 1. Nematus dimldiatus. (larva). 

 2 & ;!. AUantus Scrophulariae. (larva). 



4. Lyda sylvatica. (larva). 



5. Croesus septentrionalis. (larva). 



Plate U.—See Art. XXV. 

 Ephemera marginata. (larva). 

 Fig. 1. a. The great dorsal vessel. 



6. The point at which the great dorsal vessel curves inward and is lost to the view. 



c. The lateral vessels which convey a portion of the blood from the anterior to the 



posterior end of the body. 



d. Some of the points at which a part of their contents is discharged into the great 



abdominal cavity. 



e. The point at which they terminate, discharging their contents into the great dorsal 



vessel. 

 Fig. 2. A portion of the great dorsal vessel. 



a. Appendages, supposed to be nervous ganglions, situated above and beneath each set 



of valves. 



b. The valves at the commencement of the expansion of the artery, when the blood is 



seen converging towards them from all points, and flowing through them into the 

 upper portion of the artery. 



c. The exterior portion of the artery, connecting the parts above and below the 



valves. 

 Fig. 3. A portion of the vessel in a state of collapse, with all the valves closed. 



a. The points of the lower valves closely compressed within the upper ones. 



c. The exterior portion of the artery, as seen in Pig. 2, c. 

 Fig. 4. A portion of the vessel in its greatest state of expansion. 



a. The lateral openings closed, while the main current of the blood is passing up the 

 vessel. 



c. The exterior portion of the artery as seen at c. Figs. 2 and 3. 

 Fig. 5. A single compartment of the great dorsal vessel in its greatest state of collapse. 

 Fig. 6. The same portion of the vessel in its greatest state of expansion. 



Plate III.— See Art. XLVI. 

 Fig. 1 . Sphinx Ligustri. (larva). 



2. Biston Betularia. (larva). 



3. Tipula oleracea. (larva). 



4. Trichiosoma lucorum. (larva). 



5. Ichneumon instigator, (larva). 



6. Anthia 6-macul3ta. (larva). Copied from Guerin. 



7. Trogosita Mauritanica. (larva). 



8. Blatta ? (larva). 



9. Cicada Fraxini. (pupa). 

 10. Perla bioaudata. (larva). 



Plate IV. 



Fig. 1. Tabanus bovinus. (imago). 



2. Sirex nigricornis. (imago). 



3. Hyilxous piceus. (imago). 



4. Acridium bipunctatum. (imago). 



5. Pentatonia dissimilis. (imago). 



6. jEgeria Apiformis. (imago). 



(In this Plate the shaded portion is the mesothorax) 



Letters in Plates III. and IV. 



A. B. Caput, head or 1st segment. 



S. T. Decaton 

 U. V. Protelum 

 W.A'. Paratelui 

 y. Z. Telum . 



a. Propes . 



e. Proala . 



i. Mesopes 



o. Metala . 



ti. Metapes . . Hind-leg, 



. 10//( ditto-, 



. Urt ditto. 



. nth ditto. 



. 13/A ditto. 



. Fore-leg. 



. Fore-wing. 



. Middle-leg. 



. Hind-wing. 



