REVIEW OF NORTH AMERICAN TRYPETINA. 213 



of figures. This was done by the addition of a number of South 

 American species, described for the sake of comparison, but the 

 figures of which I would have preferred now to replace by those 

 species from North America, which I received after the plates 

 were printed. 



The critical examination of the species described by other 

 authors, appended to the first volume, p. 57-61, required several 

 corrections and additions. I have, therefore, reproduced it, thus 

 amended, at the end of the present volume, as Appendix I. 

 Appendix II contains descriptions, by other authors, of species 

 not known by me and not contained in Part I. 



The materials for the present publication, as far as the North 

 American species are concerned, are principally, almost exclu- 

 sively, derived from the communications of Baron Osten-Sacken. 

 If I had had a similar support from more than one side, my work 

 might, of course, have been more complete and more perfect. As 

 it is, I have been compelled to draw the descriptions of several 

 species from single, often badly preserved, specimens, and I am 

 afraid that these descriptions, as well as the opinions expressed 

 by me on the systematic position of some species, may sometimes 

 betray the incompleteness of my materials. I trust that an equi- 

 table critic will bear these circumstances in mind in framing his 

 appreciations. 



H. LOEW. 

 Gubex, August, 1873. 



