INTRODUCTION TO VOL. 11. 



There is little to add to the Introduction issued with the first 

 A olume of this work. 



iSince that time various small, but interesting collections oi' 

 Orthoptera have been received for the Museum, of which that 

 formed by the Tibet Expedition (few in number, but of con- 

 siderable scientific interest) and a .series collected by Mr. \\ . 

 Foster in Sajnicay, Paraguay, deserve special mention. The 

 collection now fills 77-4 drawers (40 Cabinets), exclusive 

 of the British Collection and Dr. ¥. D. Godman's Central- 

 American Collection, which occupy ') and 15 additional drawers 

 respectively. 



The present volume includes the Achet'ulce or Crickets and the 

 Pliasgonuridce or Long-horned Grasshoppers, often improperly 

 called Lonistidce. The true LocKstidep, or Short-horned Grass- 

 hoppers (often called Acridiidai), will form the third and 

 concluding volume of this work. 



The Achetidce have hitherto been somewhat neglected, but 

 our classification is based on that employed by H. de Saussure 

 in his monograph, "Melanges Orthopterologiques, 5"^^ et 6™' 

 Fascicules/' published in the ' Memoire.s do la Societe de 

 Physique et d'Histoire Naturelle de Geneve,' tome xxv. (187G- 

 1878), the most comprehensive work on this family which has 

 yet appeared. 



The Pliasgonvridir have been classified in accordance with 



