CHAPTER IV. 



PHYLUM ARTHROPODA* 



Segmented animals generally with a firm external skeleton, 

 jointed appendages, and foot-jaws. The general disposition of the 

 chief organs is the same as in Annelids, but the coelom, though 

 present and discharging important functions, does not develop a 

 perivisceral portion. The perivisceral cavity consists entirely of 

 blood-sinuses. 



THE relationship of the Arthropoda to the Annelida has led to 

 their classification in one group, the Annulosa of M'Leay. 



* The literature on the Arthropoda is referred to under the headings 

 of the several groups. There are however two topics dealt with in this 

 section, to the literature of which it may be convenient to the reader to 

 have his attention drawn. 



On the segmentation of the Arthropod head and other cognate ques- 

 tions see : 



K. Kishinouye, Note on the coelomic cavity of the spider, Journ. Coll. 

 Sc. Tokyo, vol. vi. (1894), p. 287. E. S. Goodrich, The relation of the 

 Arthropod Head to the Annelid Prostomium (Q.J.M.S., vol. 40, 1898, 

 p. 247). E. R. Lankester, The structvire and classification of the Arthro- 

 poda, Q.J.M.S., vol. 47 (1904), p. 523, reprinted from the Encyclopaedia 

 Britannica, Tenth Ed., New Volume I.. 1902, Article Arthropoda. R. 

 Heymons, Die Entwickehmgsgeschichte der Scolopender, Zoologica, Heft 

 13 (1901). Essays by G. H. Carpenter on the relationships between the 

 classes of the Arthropoda, Proc. E. Irish Academy, vol. 24 B. (1902-4), 

 p. 320 (in which a bibliography of much recent work bearing on the 

 matter will be found) and Segmentation and Phylogeny of the Arthro- 

 poda, with an account of the maxillae of Polyxenus, Q.J.M.S., vol. 49 

 (1905-6), p. 469. Sedgwick A., A monograph on the development of 

 Peripatus capensis, Q.J.M.S., vols. 25-28 (1885-8). 



On the Eyes of Arthropods see : 



Lankester and Bourne, The minute structure of the lateral and central 

 eyes of Scorpio and Limulus, Q J.M.S., 1883, p. 177. Watase, S., On the 

 morphology of the compound eyes of Arthropods, Studies from the Biolo- 

 gical Laboratories, Johns Hopkins University, iv (1889), p. 287. Kishi- 

 nouye, K., On the development of Araneina, Journ. Coll. Sc. Imp. Univ. 

 Tokyo, vol. 4, pt. 1, 1891. Grenadier, H., Unt. uber das Sehorgan d. 

 Arthropoden, Gottingen, 1879. Exner, Sig., Die Physiologic der facettirten 

 Augen von Krebsen u. Insecten, Leipzig u. Wien, 1891. Chun, Atlantis, 

 Zoologica, Bd. vii. Heft, 19 (1896). Parker G. H., The retina and optic 

 ganglia in Arthropods, Mitth. aus d. zool. Stat. zu Neapel, Bd. xii, 1897, 

 p. 1. Szczawinska, \V., Contrib. a 1'etude d. yeux de quelques crustacees 



. . Arch. Biol, T. 10, p. 523. 



314 



