ART. 11 SOME BURGESS SHALE FOSSILS — HUTCHINSON 23 



Phylum ARTICULATA 



Triploblastic metamerically segmented animals, with more than 

 three segments, skeleton primarily ectodermal, mouth and anus both 

 may be derived from blastopore. 



(a) Subphylum ANNELIDA 

 (h) Subphylum and class Onychophora 



Articulates with cylindrical leglike walking appendages arranged 

 segmentally and armed with terminal claws; body wall soft, muscu- 

 lar, indistinctly segmented and annulated with rings of papillae; in 

 recent forms coelome reduced, heart ostiate, cilia confined to genera- 

 tive ducts. 



Order 1. PROTONYCHOPHORA 



Extinct marine Onychophora with a terminal mouth, a frontal 

 papilla and clawless branched appendage followed by a series of legs 

 bearing six claws. 



Family Aysheaidae Walcott. Middle Cambrian. British Colum- 

 bia. 



Order 2. EUONYCHOPHORA 



Terrestrial Onj'^chophora with a tracheal respiratory system. First 

 three somites bearing preoral antennae and two postoral modified 

 legs which form jaws and slime papillae, frontal organs vestigial in 

 embryo. Trunk legs with a complex foot and two claws. 



Family Peripatopsidae Bouvier ; recent ; temperate southern hemi- 

 sphere. 



Family Peripatidae Evans ; recent circumtropical. 



(c) Subphylum ARTHROPODA 



BIBLIOGRAPHY 



BoxnaEK, E. L. 1907. Monographie des Onychophores. Ann. Sci. Nat. Zool., Sci. 

 9, vol. 2, p. 1. 



Bbtjes, C. T. 1923. The Geographical Distribution of the Onychophora. Amer. 

 Nat., vol. 57, p. 210. 



Evans, R. 1901. On the Malayan species of Onychophora, part 2. The De- 

 velopment of Eoperipatus weldoni. Quart. Journ. Micros. Sci., vol. 45, p. 41. 



Handlirsch, a. 1925. Phylogenie oder Stammesgeschichte, pp. 339-340, in C. 

 Schroder, Handbuch der Entomologie, III. Jena. Gustav Fischer. 



1926. Arthropoda; Allgemeine Einleitung in die Naturgeschichte der 



Gliederfiisser. p. 244, in W. Kiikenthal and T. Krumbach, Handbuch der 

 Zoologie, vol. 3, pt. 1, Berlin and Leipzig. W. der Gruyter. 



Heymons, R. 1928. Uber Morphologic und Verwandtschaftliche Beziehuugen 

 des Xenusion anerswaldae Pomp, aus dem Algonkium. Zeitsch. f. Morph, 

 und Okol. der Tiere, vol. 10, p. 307. 



