OPHRYDE^—SERAPIADINjE—OPURYS 233 



by Linnasus in Systema Natura, ed. 10, 1759, to arachnites. O. insectifera 

 Arachnites a Haller, Ic. pi. Helv. p. 26. 



HMet's fadpra only dated from 1795, and included 0. apijera. It was long fore- 

 stalled by Richard and Lamarck. Arachnites was used by a long series of authors, and 

 it is difficult to see how the substitution oi fuciflora by the elder Reichenbach in 1830 

 can be justified. Haller says it becomes notably changed during the summer. The 

 median tooth of the labellum is bent back against the concave face of the latter, so 

 that the outline appears to be continuous and without appendix ! He thought that 

 his O. fuciflora changed into 0. apijera later in the year. 



Fertilisation. On May 12th, 1929, my wife and I were carrying home the earliest 

 opened spikes of 0. arachnites at Challes-les-Eaux, France, when a grey bee with long 

 antennas came to the flowers in my hand, and after much hesitation alighted on one. Im- 

 mediately another bee of the same kind pounced on him and tried to push him off, but 

 he held on, and his assailant flew away. We then watched the first bee, and saw him 

 withdraw the two pollinia, attached to his head, and fly away. We kept perfectly still. 

 Several similar bees circled round and sometimes alighted but never stayed. Weary 

 of waiting we moved away, but a bee followed us and settled on a flower in my 

 wife's hand. I boxed him just as he had withdrawn the pollinia, and he was identified 

 at the Paris Museum as Eucera tuherculata Y. ^, He tried hard to scrape the pollinia 

 off with his feet, and succeeded in getting rid of one of them. 



The next day several similar bees came to the flowers but did not alight. The 

 following day we took the flowers down to the gate where we first encountered the 

 bees. In a few minutes at least five Eucera appeared, circled round the flowers and 

 made off". They had quickly become aware of the presence of 0. arachnites, though it 

 has no perceptible smell. At intervals single bees arrived, and two settled on the 

 flowers. I watched one carefully. He seemed to be exploring the turned-up appendix 

 at the apex of the lip with the tip of his abdomen, which he kept moving actively 

 about. On May 23 rd we again took fresh flowers to the gate. A few Eucera appeared, 

 but were manifestly less keen. Only three alighted, and these left at once. After 

 that no more came to the flowers. The previous year we had seen the same kind of 

 bee come several times to flowers held in the hand, but I was unable to catch one. 

 We noted the promptness with which Eucera became aware of the presence of 

 O. arachnites, and its excessive wariness and caution. It entirely ignored 0. muscifera, 

 aranifera and litigiosa, as well as various species of Orchis, Aceras, Eistera and Cephalan- 

 thera, exposed at the same time with O. arachnites. In both years the bees suddenly 

 ceased to appear about the same date. From observations made on various species 

 of Ophrjs in S. Europe and N. Africa, this appears to be due to the emergence of the 

 females from the pupa state, which happens some time after the males appear. Hence 



GEO JO 



