^^(, A CENTURY OF PROGRESS IN THE NATURAL SCIENCES 



genera. By 1908 some 352 species of Mesozoic and 2,559 species of Cenozoic 

 beetles had been described, nearly all from Europe and North America. Beetle 

 fossils, however, consist almost exclusively of impressions of elytra and pronota. 

 In view of the slight extent to which characters drawn from these parts are de- 

 cisive in the classification, A. liandlirsch (b. 1865, d. 1935) in his Fossilen In- 

 sekten (1908) suggested that, so far as the Mesozoic remains were concerned, 

 the record revealed no more than the presence of certain general coleopterous 

 types, such as carabid, elaterid, buprestid, and hydrophilid. The Tertiary re- 

 mains, however, even as far back as the Eocene, continue to be placed in such 

 living genera as Lehia, Harpalus, Bemhidion, Platynus, Berosiis, Tropisternus, 

 Bledius, Lathrohium, Cryptocephglus, and Sitona. 



So far as the elucidation of interglacial and postglacial remains of beetles 

 is concerned, a good deal of progress is being made by a more intensive study 

 of the characteristics of the elytra and pronotum of living species. Much further 

 back in the geological record than this, however, the writer feels that coleopter- 

 ists probably must be satisfied with form-genera, many of which may never be 

 integrated satisfactorily in the classification of living types. 



In 1924, Tillyard (Proc. Linn. Soc, New South Wales, 49:429-435, 1924) 

 described six species of Coleoptera from the Upper Permian of New South 

 Wales along with a beetlelike wing cover exhibiting true venation, which he 

 ascribed to a new order, Protoeoleoptera, close to the ancestry of the Coleoptera. 

 A. V. Martynov (b. 1870, d. 1938) in 1933 reported beetles from the Permian 

 of Russia, and Jeannel (1947) erected a suborder Archicoleoptera for these 

 Permian beetles. Jeannel, furthermore, lias shown considerable enthusiasm for 

 the Gondwanaland hypothesis and Wegener's "wandering continents" as an aid 

 in understanding beetle distribution, but there are many who disagree with him. 



Prognostication of the future of coleopterology is uncertain. If it follows the 

 pattern of a relatively mature science like ornithology, the time will come 

 when beetles everywhere, in both adult and larval stages, will be as well known 

 as are now the adult stages of central and northwestern Europe. The geographi- 

 cal variability and the ecological relationships of the species, likewise, will be 

 worked out. Many years will be required to realize such a program ! 



STREPSIPTERA 



R. M. BOHART 



University of California. Davis 



The status of knowledge in the order Strepsiptera in 1853 is indicated by 

 the fact that only 5 of the 23 currently known genera had been described 

 and these represented only 3 of the 5 families as we now know them. Some 

 two dozen authors had contributed descriptions and figures dealing with a total 

 of 11 species but had devoted most of their publications to a discussion of the 

 phylogenetic relationships of these peculiar insects. The first strepsipteran was 



