1873.] 45 



On new or little kii^ow]!^- spectes of Pitasmidjs. Part I, — Oenus 

 Bacillus, — by James Wood-Mason of Queen's College, Oxford. 



(Read 7fcli August, 1872 j received February 9th, 1873). 



[With plates V, YI and VII.] 



The difficulties that have hitherto defied all attempts at anything like 

 a philosophical and natural classification of this interesting and truly 

 remarkable family of Orthopterous Insects, although in a great measure due 

 to the extraordinary extent to which protective modification has involved all 

 parts of the body throughout the group, must be in part, at any rate, ascrib- 

 ed to our ignorance in so many cases of the opposite sexes of the species ; and 

 the discovery that Acanthoderus lacertinus, Westw. is the female of Lonchodes 

 luteoviridis of the same author, renders it extremely probable that these lat- 

 ter difficulties will be found to be farther complicated by other cases of the 

 same nature. As instances of the value of a knowledge of the opposite sexes 

 in the limitation of genera, I need only adduce the fact that the capture of 

 Acanthoderus hicoronatus, West., and Acanthoderus semiarmatus, Westw., 

 in copula with their respective males will necessitate the removal of those 

 species, together with their allies, to the genus Lonchodes. Thus at the very 

 outset of my researches, I am enabled, by the inestimable advantage of a resi- 

 dence in the great distributional area or metropolis of the family, to with- 

 draw from a genus some of the most bizarre of its extremely heterogeneous 

 contents. Since the publication in 1859 of Professor Westwood's classical 

 Monograph of the family, a large number of new or imperfectly known spe- 

 cies has been described or remarked upon by various authors,* but chiefly by 



* Giebel, Zeitsclirlft fiir d. gesammt. Naturwissensch. xviil, p. 113. 



Stal, Ofversigt af Kon. Veteusk. Akad. Forhand. xv, p. 303. 



Coquerel, Ann. Soc. Entom. Fr. 1881, p. 495, pi. 9, fig. 1 j Bull. Soc. Ent. Fr. 

 1866, pp. xxiii-xxiv. 



Westwood, Froc. Ent. Soc. Lond, 1864, p. 16 j Ann. Soc. Ent. Fr. 4e Ser. t. iv, 

 pi. 6. 



Walsh, Proc. Ent. Soc. Phil., iii, p. 409. 



Philippi, Stettin Ent. Zeit. 1865, p. 64. 



Murray, Ann. and Mag. N. H. 3rd Ser. xviii, p. 265-268. 



Kaup, Proc. Zool. Soc. Lond. 1866, pp. 577-578. 



Scudder, Proc. Bost. Soc. Kat. Hist, xii, pp. 99 and 340. 



Lucas, Ann. Soc. Ent. Fr. 4me Sei-ie, t. ix, Bulletin, p. xxv- 



Gorsta)Cker, Archiv fiir Naturgesch. xxxv, p. 211. 



