1969] 
Carpenter — Fossil insects 
421 
slender ; R4 + 5 arising slightly nearer to the arculus than to the 
nodus; other venational details are shown in figure 1. 
Holo’type: No. 165874, U. S. National Museum, Smithsonian 
Institution, Washington; found in rock forming part of the “Maw- 
son Tillite” and collected on Carapace Nunatak, Antarctica, by 
H. W. Borns, Jr. and B. A. Hall. 3 The rock matrix is part of a 
volcanic mudflow and it includes many remains of Conchostraca, 
Ostracoda, and other Crustacea, as well as numerous body frag- 
ments of insects; the latter are unidentifiable even to ordinal level, 
though some appear to be parts of aquatic nymphs (possibly mayflies 
or stoneflies). The plants of the Carapace Nunatak tillite are 
cycads and conifers and they are indicative of Jurassic age (Town- 
row, 1967). This is consistent with the occurrence of the family 
Liassophlebiidae, which is known only from Jurassic deposits. 
The specimen consists of a single wing, quite clearly but peculiarly 
preserved. The wing has been torn just beyond the nodus in 
such a way as to make it difficult to trace the subnodal vein, 
although its approximate position is obvious in the fossil. As a result 
of tearing along the posterior margin, the distal portions of 
the veins in the posterior half of the wing are not perfectly 
aligned with the basal portions, though the amount of shift is not 
uniform. Nevertheless, the use of large photographs has enabled 
the preparation of a drawing of the wing, shown in figure 1 ; this 
drawing includes only those structures that are visible in the fossil, 
except for the very apex, which is indicated by dotted lines. One of 
the peculiar features of this specimen is the preservation of the veins 
on the two counterparts: apparently, the convex veins are well 
preserved on one half and the concave veins on the other. Such a 
separation of the convex and concave veins can be duplicated in 
Recent insect wings by separating the two membranes just after 
the adult has developed its wings or by the use of caustic potash. 
Some wing veins in the fossil are only faintly indicated on the rock 
but they become very clear if the specimen is moistened with alcohol 
or glycerin-alcohol. The thin antenodals, for example, cannot be 
discerned unless the fossil is treated in this way. It is possible that 
the use of glycerin-alcohol on the specimens of Liassophlebia , which 
are in the British Museum, might also reveal the presence of faint 
antenodals in the costal area, since they do occur in the subcostal 
area (Tillyard, 1925). Even if this should prove not to be the 
case, the similarities between the wings of Liassophlebia and Cara- 
3 For the location of this Nunatak, see Borns and Hall, 1969, p. 871, fig. 1. 
