DESCRIPTIONS OF PLATES. 651 



opened sexual apparatus, seen from above. The external valves are removed. 

 a a, The internal valves, b 6, The horny penis, consisting of two parts, bent 

 outwards. 



PI. XXVII. Fig. 1, Ovaria of Ephemera marginata. Fig. 2, Of Pliasma 

 gigas (Miiller). Fig. 3, Ditto of Gryllus migratorius. Fig. 4, Ditto of Meloe 

 proscarabeus. Fig. 5, Ditto of Gryilotulpa vulgaris (ib.). Fig. 6, Ditto of 

 Lepisma (Trev.). Fig. 7, Internal sexual organs of Hippobosca (L. Duf.). 

 a , Ovaries, b, Uterus, c c, Conducting vessels. Fig. 8, Ovary of Anthi- 

 dium (Suckow). Fig. 9, Ditto of Tinea Evonymella (ib.). Fig. 10, Ditto of 

 Musca carnaria (ib.). Fig. 11, Ditto of Aphrophora spuma)'ia(ib.). Fig. 12, 

 Ditto of Lucanns parallelopipedus (ib.). Fig. 13, Uterus without appendage 

 of Tipula crocata (ib.). Fig. 14, Ditto, with an appendage of Anthidium mani- 

 catuin. a, The spermatheea (ii.). Fig. 15. The same of Hydrophilus piceus 

 (ib.). a, The spermatheca, into which the serpentine gum-vessel evacuates. 

 Fig. 16, The same of the Melolontha vulgaris (ib.). a, Spermatheca. b, gum- 

 vessel. The pockets are at the end of the sheath, into which the knob of the 

 penis inserts itself. Fig. 17, The same of Xylocopa (ib.). a, Spermatheca. 

 b, Gum-vessel. Fig. 18, The same of Sirex (ib.). a, Spermatheca, with the 

 two ears, b, Gum- vessel. Fig. 19, The same of Harpalus ruficornis. a, 

 Sack-shaped distended sheath, b, Gum-vessel. 



PI. XXVIII. Fig. 1, Uterusof Lucanus (Suckow). a, Spermatheca. d d, 

 Double gum-vessel. Fig. 2, Ditto of Gryllotalpa vulgaris (ib.). a, Sperma- 

 theca. b b, Gum-vessels. Fig. 3, Ditto of Lepisma (Trev.). b b, Gum-bags. 

 Fig. 4, Duct of the internal genitalia, with its appendages, of Gastropacha Pini 

 (Suckow). a, Spermatheca, with its narrow duct, b b, Glue-vessel, forked 

 above, beneath distended into a bladder, c c, Second secreting vessel, probably 

 a urinary organ, corresponding to the poison vessel of the Hymenoptera. a, 

 Colon and coecum. Fig. 5, Poison-vessels of Vespa crabro (ib.). a a, Secret- 

 ing vessels, b, Poison-bladder. Fig. 6, The same of Apis mellifica(S\\a.mm.}. 

 a a, Secreting vessels, b, Poison-bladder. 



PI. XXIX. Fig. 1, United testes, with the two outlets, of Pontia BrussictE 

 (Herold). Fig. 2, Testes of Libellula (Suckow). Fig. 3, Ditto of Aphrophora 

 spumaria (ib). Fig. 4, Ditto of Tipula crocata (ib.]. Fig. 5, Ditto of Ranatru 

 linearis (ib.). Fig. 6, Half of the poison vessel of Apis mellifica. Fig. 7, 

 Testes of Dyticus marginalis. a, Large knob. b, Small knob of the duct. 

 Fig. 7, b, Testes of Silpha obscura (L. Duf.). Fig. 8, Ditto of Hydrophilus piceus 

 (Suck.). Fig. 9, Ditto of Trichodes (ib.). Fig. 10, Ditto of Locusta viridis- 

 sima. Fig. 11, Ditto of Staphylinus (L. Duf.). Fig. 12, Ditto and duct of 

 Musca deviens (Suckow). Fig. 13, Ditto of Semblis bicaudata (ib.). Fig. 14, 

 Ditto of Apate (L. Duf.). Fig. 15, Ditto of (Edemera (ib.). Fig. 16, Ditto 



