[163] Phil. Trans., 1874, p. 757.
[164] The crystals have been supposed to consist of oxalate of lime (Duchamp, Rev. des sci. nat. Montpellier, Tom. VIII.). Hallez observes that they are prismatic, with rhombic base, the angles truncated. They are insoluble in water and weak nitric acid, but dissolve rapidly in strong sulphuric acid without liberation of gas, and still more rapidly in caustic potash. (Compt. Rend., Aug., 1885.)
[165] It is usually stated that the spermatheca of the Cockroach opens into the uterus, as it does in most other Insects, but this is not true. Locusts and Grasshoppers have the outlet of the spermatheca placed as in the Cockroach; in other European Orthoptera, it lies upon the dorsal wall of the uterus. (Berlese, loc. cit., p. 273.)
[166] It is a striking proof of the sagacity of Malpighi, that he should have observed in the Silkworm the spermatophore of the male (“in spiram circumvolutum persimile semen”) and the spermatheca of the female. His reasoning as to the function of the spermatheca wanted nothing but microscopic evidence of the actual transference of spermatozoa to establish it in all points. Audouin and Siebold supplied what was wanting nearly two centuries later, but they mistook the spirally wound spermatophore for a broken-off penis, and Stein (Weibl. Geschlechtsorgane der Käfer, p. 85) first arrived at the complete proof of Malpighi’s explanation.
[167] The descriptions and figures of the reproductive appendages of female Orthoptera by Lacaze-Duthiers (Ann. Sci. Nat., 1852) are so often consulted, that it may be useful to explain how we understand and name the same parts. In pl. xi., fig. 2, 8′ and 9′ are the 8th and 9th terga; the anterior gonapophyses are seen to be attached to them below; a (figs. 2 and 4) is the base of the same appendage, but the twisted ends are incorrect; the 8th sternum is seen at the back (figs. 2 and 4); a′ represents the outer, f the inner pair of posterior gonapophyses.
[168] We propose to notice here the chief differences which we have found between the figures of Brehm (loc. cit.), which are the fullest and best we have seen, and our own dissections.
Figs. 10, 11 (pp. 169–70). The ejaculatory duct and duct of the conglobate gland are made to end in the penis (infra, p. 178).
Figs. 14, 15 (p. 173). These figures seem to us erroneous in many respects, such as the median position of the penis and titillator.
Fig. 16 (p. 174). The pair of hooks marked E are too small, and there are additional plates at the base, which are not figured (see our fig. [102]). F (of our fig.) is omitted.
[169] In Blatta germanica the testes are functional throughout life. They consist of four lobes each. The vasa deferentia are much shorter than in P. orientalis.