Under the head of general zoology comes my own personal study 

 of the food and feeding habits and structures of several families of our 

 fishes, — to which much time was given in the winter of 1887-88. — 

 and the preparation of a general summary and discussion of the 

 whole series of papers on this topic published by me since 1880. 



Minor labors in the same general field are a study of the species 

 of harvestmen (Phalangidce) of Illinois by Mr. Weed, on the 

 anatomy and histology of certain crustaceans of subterranean habit 

 by myself, and on the leaf mites of the State by Prof. Garman. 



Entomology. 



The entomological work of the past two years has been almost 

 wholly economic in its objects, but incidental to the study of insect 

 injuries to agriculture, a considerable mass of information and ma- 

 terial has been accumulated, of more general entomological interest. 



The purely economic work has been extraordinarily heavy and 

 exacting, due especially to a wide-spread and very destructive out- 

 break of the chinch bug, now but just disappearing. We have kept 

 the infested area, both in southern and northern Illinois, under in- 

 spection during the whole two years, making repeated visits to 

 selected localities for comparative observations in the field. At Edge- 

 wood, in Effingham county, and at Tonti, in Marion county, we have 

 conducted field experiments for the protection of wheat against 

 chinch bug injury — in the former instances with great success, in the 

 latter with only partial results, owing to the winter-killing of the 

 grain. At the office we have made numerous tests and experiments 

 with insecticides. 



During the summer and autumn of 1888, we have collected a 

 very large amount of information from every part of the State con- 

 cerning the effect on the chinch bug of different crops and combin- 

 ations of crops, with especial reference to wheat culture, and have 

 collated, tabulated, and discussed this information, deriving from it 

 important practical generalizations with respect to farm management 

 during the progress of a chinch bug uprising. 



We have also diligently studied three forms of contagious dis- 

 ease to whose virulent activity in the southern part of the State is 

 chiefly due the rapid disappearance of the larger part of the chinch 

 bug hosts infesting that region, — a difficult and laborious research 

 which is still in progress. 



Next to the chinch bug, the Hessian fly and the corn plant louse 



