INTRODUCTION. 1x 
ciently distinct from that of Southern Mexico is very doubtful, although an inspection 
of the localities accompanying each species mentioned in the body of the work shows 
that at present the two are very distinct. For instance, Guatemala has nearly 200 
species of Aleocharine, while South Mexico has only 60; but this discrepancy loses all 
importance when we consider that our collections from the two provinces are from 
different sources. The Aleocharine are chiefly minute, obscure insects; and while in 
Guatemala Mr. Champion collected them with a perseverance and care that cannot be 
too much admired, in Mexico they have been almost completely neglected by the 
collectors who accumulated our materials. On the other hand, Guatemala, when 
compared with Tropical Mexico, appears to be deficient in the larger and more remark- 
able Staphylinide ; but then we must recollect that Mr. Champion was only two seasons 
in Guatemala, while in Mexico several collectors have for many years amassed all they 
could find of these more attractive and conspicuous forms. I therefore think it 
extremely probable that more uniform and exhaustive collecting in Tropical Mexico 
and in Guatemala will show that it would be a natural course to merge these two of 
my provinces into one. 
A similar discrepancy of collecting exists in the case of my two southern provinces, 
Nicaragua (including Costa Rica) and Panama; and I do not think, taking this into 
consideration, that the Staphylinide need be looked on as offering any impediment to 
the two provinces being treated as one, of which the northern part is the centre of 
endemicity. 
From the observations I have made I hope it will be perfectly understood that our 
knowledge of the Central-American Staphylinide is still very incomplete; because 
statistics and tables might be drawn up from them which would give quite a false idea 
of the relations of its faunistic provinces to one another. To emphasize this imper- 
fection of our knowledge, I may call attention to various anomalies that will be evident 
to those acquainted with the family and who will make an inspection of our localities ; 
e. g. North America and Guatemala have each five species of Thinobius, but neither 
Northern nor Southern Mexico has any representative. 
I shall not make any further remark in reference to the distribution of the genera 
of Staphylinide of our subregion, because not only is the imperfect collecting I have 
alluded to above a barrier to their use, but also because in this difficult family the 
genera have been much less scrutinized, and can scarcely be looked upon as of equivalent 
importance with the genera of other families in which the structural characters are 
much more easily observed. As a result of this it would appear that a large proportion 
BIOL. CENTR.-AMER., Coleopt., Vol. I. Pt. 2, November 1887. b 
