VI PREFACE. 



stage of his proposed Natural History expedition to the 

 South Seas, only a part of this book had passed through the 

 press, and had had the advantage of his personal revision. 

 At a much later period, and after considerable delay (the 

 reasons for which are given in a note received from Henry 

 Bradshaw, Esq., King's College, Cambridge, which will be 

 found at page ix.), it became my duty to assume the 

 responsibility of supervising its completion. This task was 

 rendered much easier by the valuable aid of Edward W. 

 Janson, Esq., of London, who kindly added or verified such 

 references to works as were not to be found in the Cam- 

 bridge University Library. 



It may be due to the author and the reader to say that 

 Mr Crotch was a hard worker; and by the aid of much 

 practical knowledge of his subject, and of its literature 

 in several languages, together with the possession of an 

 unrivalled collection which he had spared no trouble or 

 expense to render as perfect as possible, and an intense 

 enthusiasm, he was able to accomplish, in a comparatively 

 short period, what might reasonably be expected to have 

 required years. During the last few months ere he left 

 England, I am aware that he often spent days and nights, 

 with but brief periods of rest, in preparing the present 

 monograph, and accumulating materials for an equally 

 elaborate one on the Family of the Erotylidce. During his 

 sojourn in the United States he must have worked with the 

 same unflinching ardour till within a short period before his 

 death, judging only by what he accomplished. On referring 

 to a letter of his sent me from San Francisco, dated Oct. 7, 

 1873, I find him saying, " I have described about 500 new 

 North American Coleoptcra, and am in fact an authority on 

 them now. I have to study CureuUonida> in the winter, 



