. An ecological study of the mayfly Chirotenetes [microform]. Éphémères; Mayflies; Flies; Mouches. 12 Clemens: Ecological Study of Chirotenetes in the rubble, and none on the rock. A series of such experi- ments was tned; the arrangement and results of a tvoical set are given as follows: I ^c 2 4-8 ^i 95-2 9'c 3 Rock 0 Rock 0 Rubble 5 Rubble 4 Stones I Stones 12 Stones 19 Rubble 20 Rock o 29-4^0 "',. 23 re 77 Sc 5 6 Stones o looSt Rubble o Rock 0 Rock 0 Rubble i6 Stones 15 In all cases the nymphs were put into the trough at the lower end In conducting the fifth test a blocking of t
. An ecological study of the mayfly Chirotenetes [microform]. Éphémères; Mayflies; Flies; Mouches. 12 Clemens: Ecological Study of Chirotenetes in the rubble, and none on the rock. A series of such experi- ments was tned; the arrangement and results of a tvoical set are given as follows: I ^c 2 4-8 ^i 95-2 9'c 3 Rock 0 Rock 0 Rubble 5 Rubble 4 Stones I Stones 12 Stones 19 Rubble 20 Rock o 29-4^0 "',. 23 re 77 Sc 5 6 Stones o looSt Rubble o Rock 0 Rock 0 Rubble i6 Stones 15 In all cases the nymphs were put into the trough at the lower end In conducting the fifth test a blocking of the screen at the lower end of the trough one day caused an almost complete cessation of current, and when the trough was examined it was found that all the nymphs except one had migrated to the upper end, close to the screen where there was a slight movement of water. This appeared to indicate that current was a more important factor than material in the selection of a habitat. The results of these experiments mdicate that the nymphs have a decided aversion to open rock and a slight preference for rubble as against small Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Clemens, W. A. (Wilbert Amie), 1887-1964. [Toronto : University Library, pub. by the librarian]
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectflies, bookyear1917
