— IJO— 



and Central American faunas so that it is impossible to decide whether a 

 miscellaneous collection of Coleoptera comes from Western Texas or the 

 adjacent parts of IMexico. A miscellaneous collection, consisting nnly 

 of about loo species but made promiscuously in semitropical Florida can 

 at a glance be distinguished from a similar collection made in Cuba or 

 any other part of the West Indies. Further, the peculiar composition of 

 this fauna at once precludes the assumption that nny agencies other than 

 the current of the Gulf stream could have been active in assisting the im- 

 migration from the West Indies. 



To find out the geographical extent of this semitropical fauna in 

 Florida was the chief object of my trip and since I was fortunate enough 

 to transverse the whole length of the region to be taken into consitlerat.on, 

 I have been able to contribute to the solution of this question. But long 

 before I got through with my trip I had come to the conclusion that in 

 the course of my first expeditions to Floritla in the \ears 1875 and 1876 

 I had been, in the vicinity of Fort Capron and other points on the Indian 

 River, in the very midst of this West Indian colony of insects without 

 capturing any of them, except, accidentally, a few stray specimens. I 

 feel quite sure that my companions and myself passed then within a few- 

 yards of places where we might have collected scores of species belonging 

 to this semitropical fauna. But at that lime we' did not know anything 

 about the peculiar mode of occurrence of this fauna. Some years later, 

 Mr. H. G. Hubbard instituted a careful search at several points on the 

 narrow strip of land lying between the ocean and the Indian River between 

 Capron and Jupiter inlet. He found then for the first time quite a num- 

 ber of these species which I now recognize as West Indian immigrants. 

 All these occured exclusively in small and isolated thickets of hammock 

 land found at wide intervals in the dense shrubbery back of the ocean 

 beach. INIr. Hubbard recognized several trees composing these thickets 

 as West Indian species, but the relation of the insects to this flora was at 

 that time not fully recognized, and some of the more striking species 

 found by Mr Hubbard were shortly afterwards described by Dr. Leconte 

 as belonging to the Floridian fauna. 



IMost of the more southern Keys are covered with semitropical 

 forest, i. e. forest composed of West Indian trees, while, as I stated be- 

 fore, the true Floridian fauna and flora are almost entirely absent. I'hese 

 islands are, therefore, by no means favorable to a study of the relation of 

 the semitropical to the true Floridian fauna. However, a stay of a few 

 weeks on the shores of Biscayne Bay fully sufficed to settle this question. 

 Here as well as on the mainland farther south and the northernmost 

 Keys (Key Largo and Elliott's Key) the Floridian flora largely infringes 

 upon the semitropical forest and reduces the same to smaller or larger 



