PREFACE TO THE FOURTH EDITION. 



Several corrections of some importance have been made 

 in this edition, mostlj^ however, verbal, due in part to changes 

 in synonymy. On p. 78, fig. 68 of the third edition has been 

 replaced by a figure of Arthrolycosa antiqua Harger. On p. 

 258 correct figures of the larva and pupa of Melitcea Harrisii 

 are given. The most important addition, however, is on p. 

 438, where a brief account of LeConte's new famil}^ Platypsyl- 

 lidce is given, and liis figure of Platypsylla castoris Ritsema 

 reproduced. On p. 597, line 20, it is stated that the mouth of 

 the Libellulidie " is not furnished witli palpi." This is morpho- 

 logically inexact, as Gerstaecker has recently stated that the 

 dragon-flies possess a one-joiuted maxillary palpus, and two- 

 jointed labial palpi. These are not of the usual palpus shape, 

 but more or less rudimentary and modified in accordance with 

 the peculiar mouth parts of these and allied insects. On p. 

 6G9, for lines 22, 23, read Macrohiotus Americanus Pack, has 

 been discovered by Rev. W. R. Cross in Maine. 



Some important changes have been made in the classifica- 

 tion of the Coleoptera. The weevils, CurcuUo7udce, should in 

 accordance with the views expressed by Dr. LeConte be placed 

 at the end of the group. The Coccinellidai and Erotylidce 

 should also in accordance with the views of Mr. G. R. Crotch 

 (Check List of the Coleoptera of America north of Mexico, 

 1874), be placed in the Clavicorn series, those and allied 

 families being placed in the following succession : — Dei'- 

 mestkhe, Endomychidce, Cioidce^ Erotylkke, Atomariido', Cu- 

 cujidce, ColydikUe, Mhizophagidai, Trogositidm, Nitkhdidce, 

 Coccinellidai, Cistelidoi, etc. At the end of the series the 

 succession of families is as follows : — Ceramhycidai, Bruchidce, 

 Chrysovielidoi, Tenebrionida', JEgicditidoi, Allecullda;, 



