1967] 
Emerson — Cretaceous Insects 
277 
time. Earlier reports of fossil termites in Paleozoic deposits are all 
incorrect because of the erroneous assignment of specimens of other 
orders to the Isoptera. However, the author is of the opinion, ad- 
mittedly speculative, that the Isoptera may have originated in early 
Mesozoic or even late Paleozoic times. 
The single forewing here described is without doubt a termite. 
Only the Isoptera have a humeral suture at the base of the wing that 
enables the wings to be easily shed at the end of the colonizing 
flight. The deciduous wings are associated with the strictly social 
life of these insects, and this Cretaceous fossil is the earliest known 
social insect, inasmuch as the Labrador horizon is of an earlier age 
than the recently described fossil ants from Cretaceous amber of New 
Jersey. 
Although the order may be determined accurately, a single fore- 
wing, although remarkably complete and well preserved ? makes the 
assignment to other higher taxa somewhat more precarious. In the 
first place, the variation in the wing venation of species and genera 
of termites, particularly primitive termites, is great compared to the 
relative invariability characteristic of many other orders of insects. 
Wing venation alone cannot be used as confidently for taxonomic and 
phylogenetic interpretation of termites as it may be for other orders. 
Slight differences of wing venation, particularly of fossils, have often 
been interpreted as indications of species or generic differences that 
are obviously false when the variability of comparable living species 
is investigated. In the second place, fossils are always fragmentary 
and show a paucity of characters as compared to abundant series of 
all castes commonly collected from the living fauna. 
In spite of the lack of other characters of the head, thorax, and 
abdomen, the author feels justified in assigning this forewing to the 
family Hodotermitidae, the subfamily Cretatermitinae, new sub- 
family, the genus Cretatermes, new genus, and the species C. car- 
penter, 1, new species. These taxa and their phylogenetic relationships 
must be considered as tentative working hypotheses until more abun- 
dant and extensive material is available for study and comparison. 
Family Hodotermitidae Desneux 
The present status of the Hodotermitidae is discussed by Emerson 
(in press). The distribution of fossil and living genera is interpreted 
by Emerson (1955, pp. 473, 482, 484, 490, 492, 498, 499, 502, 506, 
507, 509, 5i6, 517). 
The author has little doubt that Cretatermes carpenteri agrees with 
the wing venation of the Hodotermitidae. The wide area occupied 
