16 OPHRE^. Chap. L 



hive -bees from ten to sixteen pollen -masses adhered ; 

 to the head of Eucera longicornis eleven, to the head of 

 Osmia rufa several, and several to the bare surface close 

 above the mandibles of Bomhus muscorum. H. Miiller 

 has seen twelve different kinds of bees visiting the 

 flowers of 0. latifolia, which are also visited by 

 Diptera. My son George observed for some time 

 plants of 0. maculata^ and saw many specimens of a 

 fly (Empis livida) inserting their proboscides into the 

 nectary ; and subsequently the same fact was ob- 

 served by me. He brought home six specimens of this 

 Empis, with pollinia attached to their spherical eyes, 

 on a level with the bases of the antennae. The pollinia 

 had undergone the movement of depression, and stood 

 a little above and parallel to the proboscis : hence 

 they were in a position excellently adapted to strike 

 the stigma. Six pollinia were thus attached to one 

 specimen, and three to another. My son also saw 

 another and smaller species {Empis pennipes) inserting 

 its proboscis into the nectary; but this species did 

 not act so well or so regularly as the other in 

 fertilising the flowers. One specimen of this latter 

 Empis had five pollinia, and a second had three 

 pollinia, attached to the dorsal surface of its convex 

 thorax. H. Miiller has seen two other genera of 

 Diptera at work on this orchis, with pollinia attached 

 to the front part of their bodies ; and on one occasion 

 he saw a humble-bee visiting the flowers.* 



We now come to Orchis (sub-genus, Anacamptis) 

 pi/ramidalis, one of the most highly organised species 



* M. M. Girard caught a front of its mouth : 'Aunalea de 



lougicorn beetle, Stranyalia atra, la Soc. Eutomolog. de France,* 



with a tuft of the pollen-masses torn ix. 1869, p. xxxi. 

 of this orchis attached to the 



