McLaughlin recently suggested (FOOTNOTE 3) that a fauna found in the lower part of the Glen Eyrie formation in the Colorado Springs Quadrangle is Marmaton, upper Des Moines, in age. This fauna consists of about twelve species of ostracodes and eight of conodonts. McLaughlin was kind enough to send the writer the ostracodes, a beautiful fauna of many well preserved specimens. He did not, however, agree with the conclusions about their age. It is the writer's belief that they are much older than Marmaton and probably Atoka-Lampasas in age; they could only be older, or slightly younger, Morrow or earliest Cherokee in age.

Although the fauna is for the greater part undescribed, it is not unknown, for almost every one of the Glen Eyrie species is identical with, or close to, such Oklahoma Atoka or Wapanucka species as Monoceratina ventrale Roth, Bairdia dornickhillensis Harlton, Amphissites wapanuckaensis Harlton, and A. rugosus Girty. Another Glen Eyrie Amphissites is clearly the forerunner of A. pinguis (Ulrich and Bassler) (A. geneae Roth) of Marmaton and later age: the nodes which persist from the early to the late molts of the Glen Eyrie and similar pre-Des Moines specimens are lost in the latest molts of their Marmaton descendants. The Glen Eyrie species identified by McLaughlin with the upper Pennsylvanian species Glyptopleura spinosa Harlton (now called G. coryelli Harlton) shows a striking resem lance to G. coryelli in the rib arrangement and is undoubtedly related to it, but both the Glen Eyrie and certain pre-Marmaton specimens now being examined consistently show small but important differences from G. coryelli: besides differences in size and spine development the rib of the Glen Eyrie species is well arched above the muscle scar while this rib is bent downward on G. coryelli. Geisina arcuata (Bean) is probably correctly identified by McLaughlin but the given range is inaccurate as Bradfield found it to be characteristic of lower Dornick Hills beds of pre-Des Moines age. Headia formosa Harlton found in the Glen Eyrie is a much misunderstood species, Marmaton forms commonly referred to this species being much smaller and with much shorter spines, and in most cases referable t the Marmaton species Healdia limacoidea Knight. The type of H. formosa is probably not from Gaptank sediments, but, as suggested by Harlton in a footnote to his original description, it is probably Dimple (Morrow) in age.

The Wapanucka-Johns Valley fauna contains many large, fancifully ornamented ostracode species, of which the slightly more conservative descendents are found in Atoka faunas. Few of these species occur in the Marmaton, and this latter formation contains many Kansas City-Canyon species, so that the contrast between the two faunas is more marked than is ordinary between Pennsylvanian faunas of so nearly the same age. The Marmaton ostracodes are among the best known faunas, assemblages of this age having been described from Nebraska, Illinois, and Missouri, and down through Oklahoma and into Texas. Most if not all of the common and typical Marmaton species are absent in the Glen Eyrie formation; also absent is the Des Moines ostracode fauna (and significantly

FOOTNOTE 3. Kenneth P. McLaughlin, "Pennsylvanian Stratigraphy of Colorado Springs Quadrangle, Colorado," Bull. Amer. Assoc. Petrol. Geol., Vol. 31, No. 11 (November, 1947), pp. 1982-2020.

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all fusulinids) found in the McCoy formation of Colorado and described by Roth and Skinner.

An Atoka age for the Glen Eyrie beds is not surprising in view of the thick pre-Des Moines beds described by Maher and others from deep wells in westernmost Kansas and eastern Colorado. These beds are not lithologically unlike the Glen Eyrie, and they also contain early Pennsylvanian ostracodes.

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