324 Sellards — Fossil Insects in the Permian of Kansas. 



tinctly Permian flora. The marked change in the insect fauna 

 in passing from the Lawrence shales to the Marion formation 

 is therefore paralleled by the plant evolution. 



From the biological side the discovery of a productive insect 

 horizon in deposits of Permian age is of the greatest import- 

 ance. Aside from the cockroaches, the number of insects 

 known from the Permian system is confined to a few interest- 

 ing specimens. The terrestrial habits of most adult insects, 

 together with their soft bodies, cause them, as a rule, to be 

 rare fossils as compared with marine shelled animals, especially 

 in Paleozoic deposits. The conditions of deposition, however, 

 during the latter part of the Paleozoic seem to have been more 

 favorable for the preservation of insects as well as of plants, 

 and thanks, especially, to the faithful researches of Scudder in 

 this country and of Brongniart and others in Europe, a good 

 deal is now known of Coal Measure insects. The degree of 

 organization of Upper Carboniferous insects indicates a much 

 earlier origin for the class, and their remains, if not already 

 found, may be confidently expected in pre-Carboniferous 

 deposits. Unfortunately there seems to be as yet no unques- 

 tioned record of the occurrence of Hexapoda back of the Car- 

 boniferous. Insects have been reported from three pre-Car- 

 boniferous localities, — Ordovician (Lower Silurian) of Sweden, 

 Middle Silurian of France, and Devonian of Canada. Regard- 

 ing the Ordovician fossil, Professor Moberg with commendable 

 frankness has written the writer that, as no more examples of 

 JProtocimex siluricus have been observed, he is now of the 

 opinion that it is not impossible that he and the entomologist 

 may have been misled by a ''lusus naturae." Brongniart, 

 although still retaining faith in the Silurian fossil Paleohtatthia 

 Douvilli^ admits that it has been regarded by some as a piece 

 of a trilobite. According to White, Kidston, and Ami, the 

 "fern ledges" at St. John, New Brunswick, heretofore 

 regarded as Devonian and from which several insects have 

 been obtained, contain a Carboniferous flora closely related to 

 that of the lower part of the Upper Carboniferous, or the 

 Meso-Carboniferous. Papers by Dr. G. F. Matthew may be 

 consulted, however, in which the deposits are referred to a 

 much earlier terrain. 



The classification of Paleozoic insects and their relation to 

 Mesozoic and recent forms are still in an unsettled condition. 

 The Permian types coming in the interval between the better 

 known forms of the Coal Measures on the one hand and of the 

 Mesozoic on the other will perhaps throw some additional light 

 on the interrelation of the older and younger members of the 

 class. 



Paleontological Laboratory, Yale University Museum, 

 New Haven, Conn., June 24, 1903. 



