ON SOME TERTIARY SAWFLIES (HYMENOPTERA, SYMPHYTA) FROM COLORADO

Through the kindness o Proessor F. M. Carpenter (Harvard University, Cambridge, Massachusetts) we have managed to locate some Tertiary sawflies originally described by Proessor C. T. Brues, Proessor T. D. A. Cockerell, and Dr. S. A. Rohwer. Since the original descriptions and illustrations o the o.ssils are no longer adequate or present needs, we have revised the descriptions, provided new illustrations, and revised the taxomic positions o the species. The drawings have been made by A. Rasnitsyn and most o the determinations by A. Zhelochovtzev. We are indebted to Proessor Carpenter for his. help in locating this material and o.r providing us with photographs o those specimens which could not be loaned.

o the determinations by A. Zhelochovtzev. We are indebted to Proessor Carpenter for his. help in locating this material and o.r providing us with photographs o those specimens which could not be loaned.
Family Xyelidae Megaxyela petrefacta Brues Figure   Megaxyela petrafacta Brues, 1908: 271. fig. 10 The distal position of the fork of SC, the straight lower margin of Imcu cell and the large size of the insect confirm the membership of this species in Megaxyela Ashmead. The species apparently differs from all Recent species ot: the genus by the narrower ovipositor, which is similar to that of Macroxyela Kirby.  Zlmass byrami: Cockerell, 1925" 10, pl. 2, fig. 5. Eopachylostictia byrami: Malaise, 1945: 14. Genus Eopachylostictia was established by Malaise (945)   The venation is similar to that of ztthalia Leach, but it differs profoundly by the strong C of the t?ore wing. Other Tenthredinidae with such a C (.some Selandriinae, Nematinae, etc.) possess quite a different venation. The ossil differs sharply from Eriocampa Hartig by its venation (especially in the region of the base of RS q-M) and by the smooth thoracic sclerites. However, too many t:eatures are indiscernable in the photograph (and probably in the holotype) to place this tossil in Ithalia with confidence.    Fenusa arva (Brues), comb. nov.

Figures 6 & 7
Lthoryssus lareus" Brues, 1906" 492, fig. 1;1908" 272. Originally this was placed by Brues in the family Orussidae, but all features are typical of Tenthredinidae and indeed of the genus Fenusa Leach (sensu Ross,951  ovipositor sheath seeming to form 5-angled-area, narrowed toward the end. Length of the body, 4.5mm; of the forewing, 4.3mm. The completely reduced 2r-rs, converged M and m-cu, the oblique 2m-cu, which may reach M only basally o.f 2r-m, and the form of the anals indicate that this insect belongs to the tribe Nematini s. str. and that it is similar to Hemichroa Stephens, Platycamgbus Schi6dte and d noplonyx Marlatt. However, the straight M, not bent at the junctions of 2r-m and 2m-cu, and the short distance between the anal cells separate it from these genera, a very oblique 2m-cu apparently from all the Tenthredinidae.    This specimen was incorrectly determined by Brues as belonging to Lithorvssus larvus (19o8: 272).

Figure 9
Scolioneura vexabilis: Brues, 1908: 262, fig. 4 Type species---Hemichroa eolhila Cockerell,19o6: Oligocene of Florissant, Colorado. First segments of antenna are long and broad, nearly as broad as the first segment of hind tarsus. In fore-wing SC occurs before R+ M, the latter is not shorter than the greatest breadth of cell It. Cross-veins 2r-r.s, 2r-m and 3r-m, as well as RS between r and 2rm are present. 2r-m is situated far behind 2m-cu, Im-cu is almost in the middle between the base of RS + M and 2m-cu. RS and M moderately diverging behind 2r-m, almost straight. Cell a is closed, the distance between it and 2a nearly equal to a half of the cell a length. First segment of hind tarsus long, a little shorter than half of the tibia.
Venation o the insect is very similar to that .of Hemichroa Stephens, and differs only by the shorter distance between the anal cells. It also differs from Hemichroa by the stout antenna, the long first segment of the hind tarsus and the more slender body.  Cockerell, 1933:

Psyche
[December differs from Neurotoma Konow by the narrow pterostigma, the more developed fore-branch of SC and the slender femora; it differs from Pamphilius Latreille by the post-ocellar area, which is enlarged forward, by the .slender femora and the impressed area at the end of the last sternite of the female; it differs from Caenolyda Konow mainly by the short fore branch of SC. It is more similar to Acantholyda A. Costa and Cephalcia Panzer but it cannot be ineluded in any of these genera with confidence since the main diagnostic features are indiscernible in the fossils. The small flagella segments (.smaller than the scape) of the fossil are more like those of d cantholyda; we therefore place it provisionally in this. genus. Figure   is based on specimens numbered 63o7-63o; figure 2 is based on the photograph of the holotype (made by F. M. Carpenter) in some deta.ils these two are not identical but the differences may be related to defects of preservation.  The reduced fore branch of SC, the broad pterostigma and the stout t:emora confirm the membership of this species in Neurotoma Konow. It differs from recent species by the occurrence of fore branches of the Y-shaped suture of the head.
Material studied: photograph of Holotype No. 8869 (American Museum of Natural History, New York), Oligocene of Flori.ssant, Colorado.