DISPERSION OF POLLEN BY ANIMALS. 163 



heir own homes which are furnished with safe retreats, and to these they with- 

 raw at dusk and in bad weather, and butterflies, for the most part, are afraid 

 seek the interior of flower-bells or funnels for any length of residence partly 

 lecause of their relatively large wings, which are liable to be injured in such 

 onfined quarters, and partly because in case of danger a rapid escape from the 

 Qside of a flower would be scarcely possible. Only beetles, flies, and Hymenoptera 

 f the genera Meligethes, Melanostoma, Einpis, Andrena, Cilissa, and Halictus 

 leed be mentioned; they are essentially nomadic in their habits, not possessing 

 lomes of their own or any settled night-quarters, but are satisfied with second-rate 

 helter, and usually pass the night wherever they have spent the day. If there 

 hould happen to be flowers there which oflfer agreeable food in addition to a warm 

 etreat so much the better. Doubtless it is for these reasons that the honey-bearing 

 )lossoms of the Bell-flowers (Campanula) and the Foxglove, the interiors of which 

 bfter sundown have a somewhat higher temperature than the environment (c/. 

 ro\. i. p. 500), are especially favourite shelters on cold nights. The large capitula of 

 Irepis grandiflora, and of several other Composites whose outer ligulate flowers 

 ilose in the evening, are also sought after by small beetles (Gryptocephalus violaceus, 

 Weligethes ceneus) and little dark-coloured bees (Panurgus u/rsinus) to serve as 

 loctumal refuges, because a higher temperature prevails at night inside the closed 

 iapitula than outside. At sunrise they abandon their night-quarters, and in doing 

 io probably — in some cases inevitably — brush off some of the pollen which they 

 !arry away and take with them on subsequent visits to other flowers. 



Sometimes insects remain in comfortable quarters of the kind not only during 

 ;he night but also during the day, and even for several days. When once the small 

 Deetles of the genera Anthobium, Dasytes, and Meligethes have ensconced themselves 

 n the interior of the flowers of Magnolias or Gentians (Magnolia obovata, M. 

 Yulan, Qentiana acaulis, G. ciliata, 0. Pneumonanthe, &c.), they do not abandon 

 ihis comfortable home till the third day. This is also true of the rose-chafers 

 [Cetonia), which have a preference for the flowers of Magnolia grandiflora. They 

 asually force themselves into the youngest flowers which are only just open and 

 take their fill of the sweet juices exuding on and between the stigmas. Later on 

 they devour also some of the pollen as it is liberated from the anthers and drops 

 apon the petals. When the Magnolia-flowers open under a bright mid-day sun, the 

 [yctonias keep still and warm themselves in the sunshine, and when evening comes, 

 md the upper petals close up, they have no inducement to leave the quarters they 

 iave chosen, for the temperature rises in the inclosed space during the night from 

 ive to ten degrees Centigrade above the temperature outside, and, besides, the Cetonias 

 ire here completely sheltered from the attacks of nocturnal animals. Thus they 

 stay in the flowers until the petals fall ofi" and leave them exposed to the air. The 

 lowers of the Opium 'PoT[>pj(Papaver somniferum) are likewise sought out by flies and 

 beetles as soon as they open, and are not deserted until the petals drop. The sojourn 

 Is, however, much shorter than in the case of Magnolia-flowers owing to the fact 

 that the Poppy only closes once for the night and loses its petals the very next day. 



