Page:Condor21(1).djvu/37

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36 THE CONDOR Vol. X"XI developments from day to day. I found that these grubs fed upon the pupae, eating shell and all, and apparently being quite indifferent as to whether the pupae contained Chalcid Fly or Muscid .larvae. From these grubs several species of moths hatched. A few living specimens of these moths were turned over to Professor Wheeler of the Bussey Institution for identification, together with some Nasonia brevicornis and Protocalliphora azurea. It was necessary to send the moths to the United States Bureau of En- tomology at Washington, where they were partially identified by Mr. Carl Hein- rich. Among them were two species of Tinea, one of which was definitely iden- tified as Tinea occidentella (Chambers). There was only one specimen of the other species and that was too badly rubbed for specific determination. A speci- men of another species proved to be an Oecophorid, probably Endrosis lacteella (D. & S.), or a closely related species, but also too badly rubbed for exact iden- tification. Several of these moths were retained for the 'United States entomo- logical collection by the entomologists at Washington. It will now perhaps be of interest to ornithologists and entomologists, as well as to bird lovers in general, to state how frequently the larvae of Protocal- liphora azurea were encountered in birds' nests and what effect their blood- sucking habit has on the nestlings. During tile eleven weeks in which these ex- periments were carried on, no less than sixty-three nests, representing six species of birds, were examined. Of these, thirty-nine, or nearly two-thirds, were in- fested by blood-sucking fly larvae. The following tables will help to illustrate. TABLE I Nests exam- Infested Uninfested Percentage Species of bird ined nests nests of tnfestation 100 Nuttall Sparrow .................................................... 4 4 0 California Purple Finch and California Lin- net .................................................................... 31 21 10 67 Green-backed Goldfinch ...................................... 13 8 5 61 Willow Goldfinch .................................................. 7 4 3 57 California Brown Towhee .................................... 8 2 6 25 Totals ............ 63 39 24 61 (Average) TABLE II Species of bird Larvae in Totals each nest California Purple Finch and California 'Lin- net .................................................................... 8, 10, 14, 15, 17, 20, 23, 29, 50, 52, 54, 60, 62, 71', 86, 94, 103, 103, 106? 108, 154. 1239 California Brown Towbee .................................. 44, 62. 106 Willow Goldfinch .................................................. 13, 24, 34, 81. 152 Nuttall Sparrow .................................................... 24, 36, 36, 37. 133 Green-backed Goldfinch ...................................... 13, 18, 19, 21, 28, 30, 35, 50. 214 Totals ............ 1844 Larvae per nest 59 53 38 33 26 47 (Average) Protocallipkora

  • A considerably smaller, but apparently more deadly species than

azurea (Fallen). From the first table it will be noticed that birds which build a rather com- pact nest, for example the goldfinches and the linnets, show a considerably larger proportion of infection than those which construct nests of a looser textare, as for instance the California Brown Towbee. This may possibly be due to the