64 ENTOMOLOGY. 



the body is flattened, and the head extended horizontally. 

 The pronotum is large, broad, and more or less square; the 



Nitsch, C. L. Die Farnilien und Gattungen der Thierinsekten 



(Germar's Mag. d. Ent., iii., 1812). 



Insecta cpizoa (Leipzig, 1874. Edited by Giebel). 



Packard, A. S. On the systematic position of the Mallopliaga 



(Proc. Amer. Phil Soc, xxiv., 1887, p. 264). 

 Piaget. Les Pediculines (Leyden, 1880). 



b. Perlidae {Plecoptera). 



Gerstaecker, A. Ueber das Vorkommen von Tracheenkiemen bei 

 ausgebildeten Insekten (Zeits. f. Wissen. Zool., xxiv., 1874). 



Hagen. H. A. Synopsis of N. A. Neuroptem. 



Newport, G. On tbe anatomy and affinities of Pteronarcys regulis 

 (Trans. Linn. Soc, London, xx., 1851). 



Packard, A. S. (External anatomy of Pteronarcys, in third report 

 U. S. Ent. Commission, 1883, p. 322, Pis. XI, XLIV, LV1I). 



Pictet, F. Histoire naturelle, etc., des insectes Ncuropteres : Part 

 I.. Perlides; Part II.,Ephemerines. (Geneve, 1841-45. With col- 

 ored plates.) 



c. Psocidae (Corrodentia in part). 



Burgess, E. The anatomy of the head, and the structure of the 



maxilla, in the Psocidae (Proc. Bost. Soc. Nat. Hist., xix., 1878, 



291). 

 Hagen, H. A. Synopsis of N. A. Neuroptera, 

 Beitrfige zur Monographic der Psociden (Stettin Ent. Zeit., 



1882). 

 Nitzsch. C. L Ueber die Eingeweidc der Bucherlaus, Psocus pulsa- 



torius (Germar's Mag. d. Ent., iv., 276). 

 Packard, A. S. (External anatomy of Psocus, in third report U. S. 



Ent, Commission, 1883, p. 325,' Pis. XXXIX, XL1II). 



d. Embidae. 



Hagen, H. A. Monograph of the Embidina (Canadian Ent , xvii., 



1885). 

 Westwood, J. 0. Characters of Embia, a genus of insects allied to 



the white ants (Trans. Linn. Soc, xvii., 369). 



See also the writings of McLachlan, Wood-Mason, etc. 



e. Termitidae (Corrodentia in part). 



Hagen. H. A. Monographic der Termiten (Linnsea Entomolog., x., 

 xii., and xiv.). 



Mtiller, F. Beitrfige zur Eenntniss der Termiten (Jena. Nat. 

 Zeitsch., vii., 1873). 



Packard, A. S. (External anatomy, in third report U. S. Ent. Com- 

 mission, 1883, p. 326, Pis. XXX1X-XL1II) 



Smeathman, H. Some accounl of the Termites, which are found in 

 Africa and other hot climates (Phil. Trans., lxxi., 1781. London). 



