THE ORCHIDS OF NEW ENGLAND. 



4? 



of the other species, is curved upwards, so that the front of 

 the flower is made somewhat tubular, and is divided into 

 "halves. Thus a moth is compelled to go to the one or other 

 side, and its face will almost certainly be brought into contact 

 with one of the discs. Professor Gray has seen a butterfly 

 from Canada with a pollen-mass of this species attached to 

 each eye." H. Hookcri has the muskiness characteristic of the 

 family but no "strong, 

 sweet odor," such as is at- 

 tributed to H. chlorantha. 

 A variety, oblongifolia, oc- 

 curs in New York State, 

 differing, as the adjective 

 implies, simply in the 

 shape of the leaves. 



The first time I analyzed ef A°poii 

 a flower of Hooker's 

 Habenaria I \._. 



the drum-like pedicel and the attached end of the 

 With the prominent beak caudicle. The disc is formed of an upper mem- 

 brane, with a layer of viscid matter beneath, 

 between the bases of the D. Side view of flower of H. Hookeri. 



anther-cells. " In both divisions of the Ophreae," Darwin says, 

 " namely the species having naked discs, and those having discs 

 enclosed in a pouch — whenever the two discs come into close 

 juxtaposition a medial crest or process, sometimes called the 

 rostellate process, appears. When the two discs stand widely 

 apart, the summit of the rostellum between them is smooth, or 

 nearly smooth." In the illustration of O. mascula, fig. 4, B, 

 D, we see the developed crest ; in the illustration of Peri- 

 stylus viridis, fig. 11, "the first stage in the formation of the 

 folded crest, the overarching summit bent like the roof of 

 a house." It is his belief that " whilst the two discs were grad- 

 ually brought together, during a long series of generations, the 

 intermediate portion or summit of the rostellum became more 

 and more arched, until a folded crest, and finally a solid ridge 



Fig. 9.— Habenaria chlorantha. (From Darwin.) 

 A. Front view of flower, a, a, anther-cells ; d, disc ; 

 *z, nectary ; «', entrance to nectary ; /, labellum ; j, 

 stigma. 



inium (this has hardly a sufficiently elon- 

 gated appearance). The drum-like pedicel is hidden 

 behind the disc. 

 Struck C ' Dia » ram giving a section through the viscid disc. 



