DEVONIAN INSECTS OE CANADA. 
457 
all the members of the Devonian series in America, and Dr. 
Dawson has lately recognized it in specimens of Old Red 
Sandstone from the north of Scotland. 
The monotonous character of the Carboniferous flora might 
be explained by imagining that we have only the vegetation 
handed down to us of one set of stations, consisting of wide 
swampy flats. But Dr. Dawson supposes that the geograph¬ 
ical conditions under which the Devonian plants grew were 
more varied, and had more of an upland character. If so, the 
limitation of this more ancient flora, represented by so many 
genera and species, to the gymnospermous and cryptogamous 
orders, and the absence or extreme rarity of plants of higher 
grade, lead us naturally to speculate on the theory of pro¬ 
gressive development, however difficult it may be to avail 
ourselves of this explanation, so long as we meet with even 
a few exceptional cases of what may seem to be monocotyled- 
onous or dicotyledonous exogens. 
Devonian Insects of Canada. —The earliest known insects 
were brought to light in 1865 in the Devonian strata of St. 
John’s, New Brunswick, and are referred by Mr. Scudder to 
four species of Neuroptera, One of them is a gigantic Ephem¬ 
era, and measured flve inches in expanse of wing. 
Like many other ancient animals, says Dr. Dawson, they 
show a remarkable union of characters now found in distinct 
orders of insects, or constitute what have been named “ syn¬ 
thetic types.” Of this kind is a stridulating or musical ap¬ 
paratus like that of the cricket in an insect otherwise allied 
to the Neuroptera, This structure, as Dr. Dawson observes, 
if rightly interpreted by Mr. Scudder, injiroduces us to the 
sounds of the Devonian woods, bringing before our imagina¬ 
tion the trill and hum of insect life that enlivened the soli¬ 
tudes of these strange old forests. 
20 
