FAM. MYCETOPHILTD^ 
85 
35. Genus THIMNA, Giebel 
Thimna. Giebel, Ins. d. Vorwelt, p. 234 (i856). 
Characters. — Head very small, eyes round; thorax large, spherical; abdomen short, cylindri- 
cal. Legs, particularly the hind pair, very long and with unarmed tibiae. Wings long and broad. Subcosta 
ends in the costa about in the middle of the wing length; very long, ending not far from the apex of 
the wing; the R-M crossvein and the second section of the radial sector together forming apparently one 
continuous vein, the true base of the radial sector wanting; media forks some distance beyond the middle 
of the wing; cubitus forks at the base of the wing; anal veins incomplete (PI. 5, Fig. 20). 
Type species : T. defossa, Brodie, described as Sciopliila defossa (fossil). 
Geographical distribution of species : 
I. T. defossa, Brodie, liist. Fossil Ins. p. 34 (121), pi. 3, f. 12 (1845). English Purbecks. 
36. Genus SACKENIA, Scudder 
Sackenia. Scudder, Bull. U. S. Geo). Geogr. Survey. Terr. Vol. 3, p. 753 (1S77). 
Characters. — Body shaped much as in Boldina. Antennas longer than the thorax, gently 
curved, 2-l-r4 jointed. Legs very long and slender; femora and tibiee of about equal length; tarsi a little 
longer than the tibia;; the hind tibiae and tarsi together a little longer than the abdomen; the tibiae with 
one or two apical spurs beneath and spined throughout. Wings rather broad ovate; the smaller veins at 
the extreme base obliterated in the specimen examined; subcostal vein terminating in the costa beyond 
the end of the basal third; Ri ends at about three-f(3urths the length of the wing; the radial sector is 
unusually curved downward at the tip so as almost to reach the apex of the wing ; the base of the 
radial sector is proximad of the tip of the subcostal vein which brings the base of the second section of 
the media rather close to the base of the wing; the cubitus forks under the R-M crossvein which is lon- 
gitudinal in position; anal vein apparently reaches the margin of the wing; the costa does not appear to 
pass beyond the tip of the radial sector, but this point is obscure (PI. 5, Fig. 21). 
This fossil genus differs from the following mainly in the elongate anal vein, and the retracted 
position of the base of the forks of media and cubitus. 
Type species : S. arcuata, Scudder. 
Geographical distribution of species : 
I. 5. arcuata, Scudder (fossil). Bull. U. S. Geol. Geogr, Survey, Terr. United States. 
Vol. 3, p. 754, fig. (1877). 
*2. S. gibbosa, Cockerell (fossil), Amer. Journ. Sc. Vol. 23, p. 285, fig. United States. 
(1907). — (Perhaps PalaeoanacUnia). 
37. Genus PAL/EOANACLINIA, Meunier 
Palaeoanaclinia. Meunier, Mon. Mycetoph. etc. p. 143 (1904). 
Characters. — Closely resemblmg Buhlina, differing only in the wing venation, the vein Scj (sub- 
costal crossvein) being absent. From Sackenia it differs in having a shorter anal vein, not reaching the 
