LIFE CYCLE AND DISTRIBUTION PATTERN OF LIPOPTENA CERVI (L.) (DIPT., HIPPOBOSC.) ON DANISH DEER.

1. The paper deals with Lipoptena cervi (L. c.). The material is from Jægerseborg Deer Park, Zealand, and consists of 1 ♀ L. c. from fallow deer, and 86 ♀♀ and 94 ♂&3x2642; from red deer, all collected from Sept.-Dec. 1960. 2. Morphology of the mouthparts makes L. c. a pool feeder (plates 1-II, Fig. 2). The claws (Fig. 3) are adapted for woollen hairs or contour hairs with diameters less than 0.22 mm. L. c. is moving sideways through the coat with head downward and almost perpendicularly to the skin. The wings are torn off by the hairs in the coat. 3. In Denmark L. c. is univoltine with appearance of a new generation in Sept.-Oct. when the red deer changes from summer to winter coat. Each healthy red deer is considered to have a carrying capacity of about 15 specimens of L. c. 4. The difference between frequency of infestation by L. c. on fallow deer and red deer is explained ecologically as a result of better chances of survival for puparium and winged stages in the habitats of red deer (woodland) than in those of fallow deer (grassland). 5. Unwinged stages show an aggregated distribution on their hosts (Fig. 5). 6. The background for aggregation is discussed with special reference to possibilities of persecution by the host, to skin temperatures (Fig. 5), and to the microstructure of the skin (plates III-VIII, Figs. 7-11). Supplementary temperature measurements on skin and in coat were made on fallow deer (Fig. 4), and cow (Fig. 6). The aggregated distribution is explained as the result of a balance between several factors (results on pp. 126-127). [ABSTRACT FROM AUTHOR]