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bulletin: museum of comparative zoology. 



in beautiful specimens representing over a hundred undescribed species 

 and was ^•ery kindly thrown open to me by the Museum authorities. 

 At the time of my visit, it was tentatively arranged in drawers accord- 

 ing to families. In some cases, a study of the specimens showed the 

 need of another assignment and in consequence the finished result of 

 the examination does not exactly agree with the provisional numerical 

 list of species by families of Dr. Scudder. For instance, there are no 

 Histeridae in the lot, though he speaks of having two. Some other 

 groups run considerably below his estimate while certain families 

 that he had not recognized at all are represented. I do not care to give 

 out complete figures in advance of w^orking over the still unstudied 

 material that I have from other sources, but it will be worth while to 

 make some remarks based upon what has been done. 



A 1 examination of the Florissant species included in the three Phy- 

 tophagous families, Cerambycidae, Chrysomelidae, and Bruchidae, 

 shows a curious state of affairs when compared with coincident assem- 

 blages in North x\merica of today. For the sake of showing this 

 readily, I have compiled a table from published lists which will indicate, 

 roughly at least, the relative specific differentiation in these families 

 in several widely separated areas. I have given also the correspond- 

 ing figures of the Florissant fossil fauna. 



This table has to do with species, not with specimens. In the sec- 

 tion devoted to relative frequencies, I have taken that of the Chryso- 

 melidae to be 100 in order to get a uniform standard of comparison. 

 It will be noted at once that the Florissant ratio between the Chryso- 

 melidae and Cerambycidae is, relatively speaking, not strikingly out of 

 proportion with that shown between these families in Ohio and the 



