SCORPIONS AND DRAGON-FLIES 
179 
according to Prof. Kolbe,* on account of its feeble development 
and weak flight. Taking into consideration the general dis¬ 
tribution of this genus, he favours the view of a former 
ancient land connection between the Antilles and North 
America. 
In its butterflies and moths Florida is united to Central 
America and the Antilles, and it is from the latter that such 
genera as Ileliconius, Dione and Agraulis gained a foothold in 
the northern continent.f 
An exceedingly ancient group are the woodlice (Isopoda) or 
“ sowbugs ” as they are sometimes called in America. In 
eastern Europe at Odessa, and again in north-western Africa, 
an interesting very peculiar species occurs which is known 
as Tylos latreilli. The same species has been met with, in 
southern Florida and in the Bermuda islands. A case of that 
kind is generally set down at once as an instance of human 
importation. The possibility of the survival of such a species 
through several geological ages is not even discussed. But 
in southern Florida a second species of Tylos has been dis¬ 
covered which occurs elsewhere only in Bermuda. This 
species, known as Tylos niveus, is white in colour and pos¬ 
sesses structural differences distinguishing it from the other. 
Of the genus Cubaris, which is widely distributed through the 
Antilles and westward to Mexico and California, a single 
species (Cubaris pisum) occurs in Florida, and is peculiar 
to it.$ 
All these, it may be objected to, are inconspicuous creatures 
that might have been overlooked elsewhere. Too much im¬ 
portance, it might be urged, should not be placed on their 
occurrence in Florida. We may return, therefore, to more 
conspicuous objects. 
Everyone in America knows, or has heard of, the alli¬ 
gator (Alligator mississippiensis), though it is only found 
in the southern states of North America. Its distribu¬ 
tion in fact is rather limited. From Florida it extends 
northward to Carolina and westward as far as tlie Rio 
* Kolbe, H. J., “ Neuroptera der Antillen,” pp. 157—158. 
t Pagenstecher, A., “ Verbreitung der Schmetterlinge,” p. 359. 
t Richardson, H., “ Isopods of North America.” 
N 2 
