146 ENTOMOLOGICAL SOCIETY 
dian colony is coincident with that of the semi-tropical forest, and Mr. 
Schwarz pointed out that in southeastern Florida this forest occupies the 
chain of the Keys, and small, more or less widely separated spots on the 
mainland as far north as the head of Biscay ne Bay. It is northwardly 
continued, however, immediately along the shore in island-like, usually 
very small, spots as far as Cape Malabar. According to the botanists the 
same conditions prevail on the southwestern coast, where the semi-trop- 
ical forest extends always immediately along the coast as far north as 
Tampa Bay. In the interior there is no semi-tropical forest except on the 
few Keys in the Everglades. This character of the semi-tropical fauna of 
Florida and its peculiar distribution is in marked contrast with the exten- 
sion of the semi-tropical fauna into the southwestern extremity of North 
America. 
The immigration of West Indian forms into Florida took place at a quite 
recent geological period and is, in fact, still going on, but must not be 
confounded with that immigration from the south which took place at the 
end of the glacial period and which shaped the character of the present 
fauna of North America. 
Mr. Schwarz finally argued the point whether or not it would be advis- 
able to include these semi-tropical species in the catalogues and monographs 
of North American insects. An inclusion of the whole Central American 
fauna is evidently impracticable, but a complete exclusion is also most in- 
convenient. Mr. Schwarz agrees with Mr. Smith that only those species 
should be included which are found breeding in our territory ; but. this 
would practically include the whole of the semi-tropical Coleopterous 
fauna occurring in Florida, and it would seem advisable to add still an- 
other restriction, viz., to exclude all those forms which in their character 
strongly contrast with the nearest representatives of the North American 
fauna and which would occupy a more or less isolated place in our mon- 
ographs and synopses. 
Dr. Horn, commenting on Mr. Schwarz's paper, said he agreed 
with him in his ideas of the derivation of this fauna. He had been 
watching it for some time, and had often been in doubt whether 
the species should or should not be included in our lists. He 
thinks not, when they introduce confusing material into our fauna, 
though species in truly temperate genera might easily be included. 
On the question of distribution he cites the fauna of Guadalupe 
Island. Here a current runs south from Alaska along the 
Pacific coast to Point Concepcion, is here deflected, and finally 
strikes Guadalupe oft' South California. Along the whole region 
the fauna is similar, and he believes is largely governed by this 
current. He also showed why the political boundary between 
the United States and Mexico was also nearly a natural one for 
