1 882.] Geology and Paleontology. 335 



Europe. It was first pointed out by myself in Eryops ( Rhachito- 

 vius) and Trimerorhachis, in the Naturalist, May and Sept., 1878 

 (p. 633), and soon after by Gaudry in Actinodon. An examina- 

 tion of the figures and descriptions given by Von Meyer (Palseon- 

 tographica) of the rather imperfect specimens of Archegosaurus, 

 led me to believe that the vertebrae of that genus possess the seg- 

 mented character also. I therefore included Archegosaurus in the 

 samenatural divisi< >n with Eryops, etc., and employed for it the name 

 Ganocephala which had been created by Owen for its reception. 1 

 It now appears from the descriptions of Dr. Fritsch that the verte- 

 bras of Archegosaurus are not of the segmented type, but that they 

 are discoidal, as in the Labynnthodontia. Under these circum- 

 stances, the suborder Ganocephala must be given up, and a new 

 name given to the suborder represented by Eryops, Actinodon, 

 etc., and which I characterized in the Proceedings of the Ameri- 

 can Philosophical Society, for June, 1880. This suborder may be 

 called the Rachitomi, and will include the following genera. 

 Trimcrorhachis ; / J\irioxvs ; Eryops ; Actinodon; Zatrachys ; 

 f Pantylus. There are two families, defined as follows : 



Occipital condyle divided into two lateral condyles Eryopida 



But one genus can yet be referred to the first family; to 

 the second belong Actinodon and probably Zatrachys, besides 

 Eryops.— E. D. Cope. 



Marsh on the Dinosauria. — Professor Marsh has published a 

 more complete systematic arrangement of these reptiles than the 

 one noticed in the March Naturalist. In this he includes many 

 of the genera described by European and American authors, and 

 gives them their appropriate positions. Genera whose characters 

 cannot be ascertained are omitted, and some synonymes are in- 



Geological News.— The Geology of Frenchman's bay, Maine, 

 is treated of by W. O. Crosby in the Proc. Bost. Soc. Nat. Hist. 

 The rocks consist of a schistose silver-bearing group, and a slate of 

 Cambrian or Primordial age. A few fossils have been found in the 



same slate at other localities. M. Daubree (Bull. Soc. Geol. de 



France) gives details of the two directions taken by joints or frac- 

 tures in the cretaceous strata near Paris. These joints are usually 

 parallel to the reliefs of the region, and the two systems are 

 nearly at right angles to each other.-— The Geological Mag- 

 azine for December, 1881, contains descriptions of some fos- 

 sil Crustacea from the Stonesfield slate of Oxfordshire, Eng- 

 land, by Hy. Woodward. Three species of Ervon and one of 

 the 'curious larval-looking genus Pahcocaris, hitherto known 

 only from the /'. typus of Meek and Worthen, are for the first time 



published. The same magazine includes articles on the Brid- 



1 Proceeds. Amer. Philosoph. Soc, 1S80, June. 



