50 Br. H. Woodward — British Carboniferous Cockroaches. 



Boston, who has not only described all the species that have come to 

 his hands from the Coal-measures of N. America, but many European 

 ones also, and has given us " a complete revision of the species of 

 both worlds " (see Mem. Boston Soc. Nat. Hist. Boston, 1879, 4to. 

 vol. iii. pp. 23-134, and plates 2-6). 



According to a still later summary on "The Cockroach of the Past " 

 (published as an appendix to " The Structure and Life-History of the 

 Cockroach (Periplaneta orientalis) ," by Prof. L. C. Miall and Alfred 

 Denny, London, 1886, 8vo.), Mr. Scudder gives the number of 

 Carboniferous Palceohlaltarice at 70 species. 



1. 



2. 



Figs. 1 and 2. — Progonoblattina [Blattd) helvetica, Heer (Swiss Cockroacli), from 

 tlie Coal-measures of Erbignon. 

 1. Wing, of tlie natural size. 2. The animal restored. 



Eeproduced from Prof. 0. Heer's PrimseTal World of Switzerland, London, 

 1876 (translated by W. S. Dallas, F.L.S.), 2 vols. 8vo. p. 20, fig. 16c. 



It must, however, be borne in mind that our knowledge of this 

 ancient type of Orthopterous Insect is derived almost entirely from 

 its wings ; and upon the well-marked variations which the principal 

 veins present in their arrangement (see Fig. 3). 



Scudder, who adopts the terminology proposed by Prof. Oswald 

 Heer, of Zurich, writes : — " These principal veins are six, counting 

 the marginal vein, which here merely thickens the anterior bordei', 

 as one ; and starting from the anterior margin, they are the marginal, 

 mediastinal, scapular, externo-median, interno-median, and anal. The 

 general disposition of these veins is as follows : — The ' mediastinal ' 

 and ' scapular ' veins, with their branches, which are superior {i.e. 

 part from the main vein on the upper or anterior side), terminate 



