OF WASHINGTON, 95 



Scardia burkerella Busck, bred from a fungus in Washington. 

 At present I prefer to retain it under a separate name. 



Washington State (Wm. Beutenmiiller). 



Type. — No. 11341, U. S. National Museum. 



A COMPARATIVE STUDY OF THE THORAX IN ORTHOP- 

 TERA, EUPLEXOPTERA AND COLEOPTERA. 



By R. E. Snodgrass. 

 (Plates II-V.) 



INTRODUCTORY. 



The anatomical facts described and illustrated in this paper 

 are presented simply on a basis of their own interest. In 

 showing that there are certain points of resemblance between 

 the Euplexoptera and the Orthoptera on the one hand and the 

 Coleoptera on the other the author does not undertake to set 

 forth the phylogeny of these orders. It is probably not impos- 

 sible that the Coleoptera may have some relationship to the 

 Euplexoptera, notwithstanding their metamorphosis, yet the 

 characters here discussed do not constitute sufficient evidence 

 for any theory of coleopteran descent. 



The material made use of is selected from data accumulated 

 by the author while working under Dr. A. D. Hopkins on 

 the anatomy of the external parts of beetles in connection with 

 Doctor Hopkins's systematic and economic work on the Scoly- 

 tidse. A more comprehensive and comparative account of the 

 insect thorax and the wing articulation is reserved for future 

 publication. 



GENERAL. 



Before going into the more special description of the forms 

 discussed it will be well to review the general anatomy of the 

 parts involved, i. e., the microthorax and the notal and pleural 

 regions of the other three thoracic segments. Probably the 

 most extensive comparative studies of the external anatomy 

 of the lower insects are those published by Verhoeff during 

 the last few years. His monograph on the morphology of the 

 insect thorax^ is the only work that will be referred to in this 

 paper. 



^ Verhoeff, K. W. — Beitrage zur vergleichenden Morphologie des 

 Thorax der Insekten. < Nova Acta. Abh. der Kaiserl. Leop.-Carol. 

 Dent. Akad. der Naturforscher, lxxxi, No. 2, pp. 63-109, Pis. vii-xiii. 



