FEMALE ORGANS OF GENERATION. 187 



and Notonecta have six tubes, each with from five to six eggs ; Veapa 

 vulgaris and Silpha atrata seven tubes ; Tenebrio, Leptura, Saperda, 

 Blatta, Ascalaphus, Bombiis terrestris, from seven to ten tubes, each 

 with from four to six eggs ; Cicindela, Carabus, Dyticus, Staphylinus, 

 Hydrophilus, Cerambyx, Lamia tristis from ten to fifteen tubes ; Bu- 

 prestis mariana twenty ; Blaps mortisaga thirty, each with four eggs ; 

 Apis mellifica above a hundred, each with seventeen eggs. 



5. OVARIA CAPITATA (PI. XXVII. f. 12). They merely differ from 

 the preceding in their short tubes not running upwards in a point, but 

 which distend into a large knob, whence the point proceeds as a thin 

 filament (Lucanus). 



137- 



The situation of these very various ovaria is nearly the same in all 

 insects, for they always lie laterally in the abdomen contiguous to the 

 intestinal canal, and fill the whole remaining space of the abdominal 

 cavity not occupied by that organ. They often lie free and separated 

 from each other, but sometimes fold over from both sides towards each 

 other, and thus form a covering over the nutrimental canal, containing 

 it between them. The latter then forces itself into the anterior portion 

 of the thus formed longitudinal canal, runs within it, and posteriorly 

 it again presents itself, passing over the common duct, which the colon 

 always covers above. Such approximate ovaria are connected by the 

 tracheae, which approach them with their large stems, and then accom- 

 pany each of their individual tubes by delicate accessory branches to 

 their very extremity. There is still another means for retaining the 

 ovaria in their place, which is their communicating duct with the 

 dorsal vessel, discovered and described by Joh. Muller *. Each indi- 

 vidual egg-tube, or occasionally the common egg bag, extends in a thin, 

 very delicate, but tolerably firm filament, which ascends anteriorly and 

 above to the dorsal vessel to discharge itself therein. This connexion 

 invariably takes place at that portion of the organ which we have 

 described as the aorta, sometimes at a great distance from the ovarium, 

 for example, in the thorax. This kind of connexion is peculiar to the 

 ovaries of the third chief division, for the connecting filaments of each 

 egg-tube unite in a cord, or frequently, prior to their connexion with 

 the dorsal vessel, they meet and form a single short tube, for example, 



" Nova Acta Phys. Med. n. c. vol. xii. part ii, page 555, &c. 



