AN ARISTOCRATIC FAMILY. 47 



ible if its operation were not plainly visible to anyone who 

 cares to look, the pollinia are capable of automatic motion. 

 At first they diverge too much and would, if inserted in 

 that position, strike one side of the stigma ; but after a few 

 seconds they begin to undergo a movement of depression 

 forward, so that about the time the insect should enter an- 

 other flower they point directly forward and will be in pos- 

 ition to strike the stigma. 



This phenomenon may be observed by anj^one who 

 can procure one of the later fringed orchids, Habena- 

 j-ja Jimbriata, psychodes or laccra, either of which may be 

 found in certain localities during the mouth of August. 

 By inserting a sharp pointed pencil or a toothpick or a 

 bristle in the direction of the nectary one or both of the 

 pollinia may be withdrawn and the movements observed. 

 It will be interesting to note how many flowers in a spike 

 have already lost their pollinia, and how many of the stig- 

 mas have had pollen brought in contact with them. The 

 best of all will be to watch an insect while he performs his 

 ofhce. 



It would be useless to attempt a description of all the 

 methods used by this aristocratic family to secure the one 

 end and aim of their existence, cross-fertilization. I will 

 name now only certain adaptations which occur within the 

 genus we have been considering, Habenaria. In some 

 species the anther sacs are so widely separated that an in- 

 sect proceeding directly to the central nectary would touch 

 neither of them. In H. Hookeri, for example, thiscontin- 

 genc}^ is provided for b}^ curving the lip upward, instead 

 of downward as usual, and also by almost dividing the flow- 

 er into halves, so that the insect is compelled to go to one 

 side or the other in approaching the nectary. In H.flava 

 {yirescens) the same end is accomplished by the production 

 on the lip of a ridge or "nasal protuberance," as Gray calls 

 it. 



