51 8 THE ANIMAL KINGDOM. 



consecutive somites. The majority of Chilopoda appear to possess the 

 full number of limbs at birth. It may be noted that the embryo of 

 Diplopoda developes one or two (htlus} cuticular envelopes. 



A sound-producing apparatus is found in the Chilopod Eucorybas 

 Crotalus and in Sphacrothcrinm. In the former the fourth joints of the 

 last pairs of limbs are expanded and leaf-like, and are rubbed together 

 by the animal. In the latter, ridges on the outer side of the middle joint 

 of the second and in 5. retusum also of the first pair of copulatory organs 

 in the male work against sharp points on the inner aspect of the last 

 tergum. There is a limited power of reproducing lost parts of the append- 

 ages. 



Extinct groups of Myriapoda appear in Carboniferous strata in 

 America. Of these Archipolypoda belonging to the Diplopoda, the Proto- 

 syngnatha to the Chilopoda. 



The Myriapoda are divisible into two orders. 



1. Diplopoda (= Chilognatha). Body cylindrical or semi-cylindrical, with two 

 pairs of feet to the middle and posterior somites ; generative apertures on the 

 basal joints of the second or third pairs of limbs. 



2. Chilopoda. Body as a rule flattened dorso-ventrally ; a ' basilar segment ; ' 

 second pair of post-oral limbs forming powerful poison claws ; one pair of limbs to 

 each somite. 



The two pairs of limbs, two ganglia, two stigmata, &c., to each somite in 

 Diplopoda appear to arise not from fusion but from imperfect division of the 

 somite. Cf. Balfour, Comp. Embryology, i. p. 234. 



' Myriapoda,' Moseley, Encyclopaedia Brit. (ed. ix.) xvii. Latzel, ' Die Myrio- 

 poden der Oesterreichisch- Ungarnischen Monarchic,' 2 vols. 1884. Cf. On Mor- 

 phology of Chilopoda, Haase, Z. A. viii. 1884 ; and On Myriapoda, Packard, A. N. H. 

 (5), xii. 1883. 



Pauropoda, Ryder, American Naturalist, xiii. 1879. 



Fossil Myriapoda, Zittel, Handbuch der Palaeontologie, Abth. i. Palaeozologie, 

 ii. pt. 5, 1885. 



Anatomy of Sphaerotherium, G. C. Bourne, J. L. S. xix. 



Sense organs of Antennae, Bourne, op. cit. supra ; von Rath, A, M, A. xxvii 

 1886; Antennal hairs, Sazepin, Mem. Acad. Imp. St. Petersburgh (7), xxxii. 1884; 

 Sensory cavities, Bourne, op. cit. supra; Tomosvary in Naples Zool. Jahresbericht, 

 1884, pt, ii. p. 132; in Scutigera, Heathcote, Q. J, M. xxv. 1885; cf. Haase in 

 Schneider's Zool. Beitrage, i. 1885. 



Hydrogen cyanide, &c. in Fontaria, Weber, A. M. A. xxi. 1882 ; Guldensteeden- 

 Egeling, Arch. f. Physiol. (Pfluger), xxviii. 1882; Cope, American Naturalist, xvii. 

 pt. i. p. 337, 1883. Sticky Secretion in Glomeris, Dewitz, Biol. Centralblatt, iv. 

 1884-85. 



Pharynx of Scutigera, Haase, op. cit. 



Respiratory organs of Chilopoda and Symphyla, Haase, op. cit, 



Genital organs and development in Geophilus, Sograf; see Naples Zool. 

 Jahresbericht, 1883. pt. ii. p. 90. 



