SUBPHYLUM II 



MYRIAPODA \ \ 793 



of Julud (tA 



and Phryssonotus Sciidder {Lophonotus Menge). A species of Julm (JV telluster 

 Scudder) occurs ki tlie Green River Eocene of Wyoming, and another in the Miocene 

 freshwater beds of Florissant, Colorado. 



The older fossil forms are referable to the two extinct Orders of Scudder, Proto- 

 syngnatba and Arcbipolypoda. The former of these approaches closely to the Recent 

 Order Pencillata, and is represented by the Carboniferous genus Palaeocampa Meek 

 and Worthen. The second of these Orders comprises three families, of which the 

 Arcliidesmidae resembles the Recent Polydesmidae. Ärchidesmus Peach (Fig. 1529); 





Fig. 1529. Fio. 1530. 



Ärchidesmus macnicoli Peach. Lower Old Red Sand- Euphoberia armigera Meek and Worth. Goal 



stone ; Forfarshire, Scotland. i/i (after Peach). Measiires ; Mazon Creek, Illinois, i/i- 



and Kampecaris Page, from the Old Red Sandstone of Scotland, are examples, The 

 family Euphoberiidae shows sonie resemblance to the Julidae of the present fauna, 

 but the dorsal scuta are more or less distinctly divided into two portions corresponding 

 with the pairs of legs. Among Carboniferous genera belonging to this family may 

 be mentioned the following : Äcantherpestes and Euphoberia Meek and Worthen 

 (Fig. 1530); Ämijnilispes and Eileticus Scudder. Äcantherpestes is regarded by 

 Scudder as probably amphibious, and attains the relatively enormous length of 

 20 cm. {A. giganteus Baldwin). The family Archiulidae is represented in the 

 Carboniferous by Trichiulus and Archiulus Scudder, and Xylohius Dawson. One 

 Mesozoic species, Julopsis cretacea Heer, from the supposed Cretaceous of Greenland, 

 is of doubtful ordinal position, but may belong to the Arcbipolypoda. 



Olass 2. OHILOPODA Latreille. (Centipedes). 



Body more or less ßattened dorso-ventrally, composed of a variable number of 

 Segments {from 18 to 176), with a single pair of legs to each segment. One pair of 

 segmented antennae, the joints being at least fourteen in number, one pair of mandibles 

 and tum pairs of maxillae. First pair of somatic appendages modified as powerful 

 maxillipeds with poison glands emerging on the terminal claw (toxognaths). Last pair 

 of appendages (those borne by the antepenultimate segment) modified as copulatory organs. 

 Unpaired genital aperture on the penultimate segment. Eyes variable in number, simple 

 or Compound (Scutigera), often wanting. Respiration by means of tracheae with either 

 p)aired spiracles in the pleural membranes or single spiracles in the median dorsal line. 



Recent Chilopoda are divided into five Orders, three of which have Tertiary 

 representatives, esjDecially in amber, and in the freshwater deposits of Aix in Provence. 

 The following true Chilopod genera are known from the Tertiary : Cermatia Rossi ; 

 Scolopendra Linn. ; Lithobius and Geophilus Leach. The older fossil remains cannot be 

 positively referred to any of the five existing Orders. By Scudder they were assigned 

 to two extinct families, named by him Gerascutigeridae and Eoscolopendridae. 

 The former of these includes the genus Latzelia Scudder, and the latter the genera 

 Palenarthrus and Ilyodes Scudder, all from the Coal Measures of Illinois. 



[The text for the preceding chapters on Embolobranchiata and Myriapoda has been revised 

 by Dr. Alexander Petrunkevitch, of Yale Uiiiversity. — Editok.] 



