CONTENTS 



CHAPTER XIX 



ARACHXIDA (API'ENUIX I) 



PAOB 



Taiidigrada — Occurrence — Ecdysis — Structure — Development — 



Affinities — Biology — Desiccation — Parasites — Systematic . . 477 



CHAPTER XX 



ARACHNIPA (appendix II) 



Pentastomida — Occurrence — Economic Importance — Structure — 



Development and Life- History — Systematic 488 



PYCNOGONIDA 



CHAPTER XXI 

 Pycnogonida 501 



INDEX 5^3 



