LARVA OF PRIVET HAWK MOTH. 147 



Festgabe zur Karl Ludwig, 1874. Gizzard of Orthoptera. Wilde, A. N. 43, 1877. 

 Appendices pyloricae. Graber, SB. Akad. Wien, lix. Abth. i. 1869. Rectum. 

 Chun, Abhandl. Senck. Gesellsch. x. 1875. 



Malpighian tubes. Schindler, Z. W. Z. xxx. 1878. 



Corpus adiposum. Targione Tozzetti, Bolletino della Soc. Entomol. Ital. iii. 

 1871; iv. 1872. Its formation in Corethra. Wielowicjski, Z. A. vi. 1883. 



Heart. Graber, A. M. A. ix. 1873. Ventral pulsatile sinus. Id. op. cit. xii. 

 1876. Blood corpuscles. Id. SB. Akad. Wien, Ixiv. Abth. i. 1871. Cf. on heart. 

 Poletajewa, Z. A. ix. 1886. 



Stigmata. Krancher, Z. W. Z. xxxv. 1880; Landois and Thelen, Ibid. xvii. 

 1877 (for P. orientalis, see Taf. xii. fig. 12). Primary number in Insecta. Packard, 

 American Naturalist, viii. 1874. Tracheal System of Insecta. Palme'n, Morphologic 

 des Tracheensystems, Leipzig, 1877. Minute Anatomy of Tracheae. Macloskie, 

 American Naturalist, xviii. 1884. 



Testes of Periplaneta. Rajewski in Hoffman and Schwalbe, Jahresbericht fur 

 Anat. und Phys. 1875, p. 425. Male genital armature of same. Huxley, Anatomy 

 of Invertebrated Animals, 1877, p. 406. 



Female organs, &c. see end of description of PI. viii. 



Histology ', Histolysis, and Histogenesis of Insecta, Viallanes, A. Sc. N. (6), 

 xiv. 1882. Cf. Ludwig, Untersuchungen zur Anat, &c. der Thiere, Bonn, 1883, 

 passim. 



Development of Blatta germanica. Rathke, Meckel's Archiv (Arch, fur Anat. 

 und Physiol.), 1832. Cf. A Note on same. Patten, Q. J. M. xxiv. 1884. 



29. LARVA OF PRIVET HAWK MOTH (Sphinx Ligustri\ 



THIS and the two following preparations are intended to illustrate the 

 various points of external anatomy in which the larva, pupa, and imago of 

 a Lepidopteron, an insect with perfect metamorphosis, differ from one 

 another. The larva (or caterpillar) belongs to the eruciform type of Packard. 

 It possesses a distinct head, but it has a somewhat vermiform appearance 

 owing to the great homonomy or similarity of the remaining somites, 

 and the fact that the segmentation of the antennae and feet, and the 

 form of the mouth-parts are not obvious to 'the unassisted eye. 



The greater part of the covering of the head is made up by the two 

 large ' parietal scales ' of Lyonet, corresponding to the epicranium of the 

 imago. A triangular plate, the ' frontal scale ' of the same author, the 

 representative of the clypeus, lies anteriorly between them. The parietal 

 scales are each marked laterally by a dark stripe, at the inferior end of 

 which may be found the six ocelli usually present in a caterpillar, as six 

 whitish spots. The antennae and mouth-parts may be seen with the help 

 of a lens. The antennae are three-jointed, and are situated below and 

 internally to the ocelli. The joints can be retracted one within the other. 



L Z 



