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.. The 'ltJAl!1 end varied ecological niches of the Green River provide a eonsid~rs.ble variety of insects. For example" one collection by l3anl:s taken on July 29 at Echo Park contained 8 different species of Mayflies trom. the families: Baet ide.e; Heptagen1idae" and ~hemeridae. These were ill addition to other orders includinG stonef ies, dragon flies" etc. Be additional specimens of the tentatively identified stonefly Acroneuria lye arias were found during the summer or autumn collections. !!!.!!. stomach ana4s is The tedious job of stomach analysis continues and will not likely be cOJl.Pleted before the fall of 1963. There is no present indicat ion that the data will provide any definite conclus ions regarding the preferred foods of any- of the :fish species encountered in the Green River. stomach contents of most species vary in accord to the insects or aquatic plants appearing in the bottom samples that lTere taken per1odic~ly. Fish remains were found in stomachs of adult forms of squav1'ish" chubs" carp" catfish" and even in the stomach of the tlannel mouth sucker in at least one instance" This was not observed in 1961. Fish remains appeared in the stomach of only the lareest bony tailed or round taU chubs. Immature fish of this genus appeared to eat only insects or plant materials. )t)st of the stomachs of the very large fish carne from specimens kUled in the September pollution. These data remain to be analyzed s1ncebundreds were collected. It is doubt:f'ul, however" that they w1ll produce much information other than that the fishes of the Green River appear to be fortuitous rather than selective feeders. Parasites and disease - III 1961, an attempt was made to record the incidence and types of external parasites and70r diseases of the several fish populations. During the summer and autumn of 1962, careful inspect ion was made of fish samples to correlate with the 1961 findings. As in 1961 three primary paras ites were found: onecopepod, Lernaea cyprinacea or "anchor worm-; one leech Mfzobdella moorei" and one sporozoan identified only to the genus ~osoma. This sporozoan produces a disease not unlike "white spot II ease or Ichthyopithirius. Clusters of these parasites gather on the sJdn,f'orm1ng white pimple-like structures. The individual sporozoans show the typical two to four polar capsules and no iodinophilous vacuole. Pour. species at fish (dace, bony tail chub, mountain Bueker, and flannel muth SUCker ) were observed to be parasitized with this organism. )t)st o-r tbe infection appeared to be in the Echo Park area of the Green River. '!'be leeeh appeared only on the channel cattish but vas very abundant on these fish. They were collected on fish from all areas. The copepod was tound on all species of fish taken in 1962 with the exception o'f the channel catt'ish, the black bullhead, the sculpin and the carp. As in the 1961 Rud1es, the carp seems to be free from the external parasites with the =6= ~-