bars, though not directly apparent in all the speoes, :s expressed 

 by the curious phenomena which have lately come under our 

 notice. Bachmani is exceedingly rare, for aught we know on 

 the verge of extinction, though it still exists in favorable localities 

 in the vast swamps of the Southern States. 



The mythical carhonata might have been the last of anotner 

 form,-who can tell .? Audubon gave it a place in this genus. 



Chrysopera and pinus yet remain fairly abundant but forced 

 apparently to cross with each other, and the resultmg forms, 

 llrencei and leucobronchialis, without doubt recross with the 

 parent species.* Further, we find evidence that finus has un- 

 doubtedly gone over to the strange genus Ofororms and con- 

 tracted an alliance there. t 



These are the facts, and we are left to draw our own conclu- 

 sions in the best way possible. Genera and species nse up, in- 

 crease and become dominant only to break down^ain under the 

 pressure of other and better adapted forms. What the other 

 genera of the Mniotiltidse may have been in the past we can only 



'"Those that now possess but one or two species may, and very 

 likely have, possessed more and been dominant in their time. A 

 change in habit under pressure and consequent structural modi- 

 fication would be of immense advantage, and finally result in one 

 or two well adapted species forming a well defined genus buch 

 may have been the history MniotiUa. Frotonoiaria, and others, 

 and such may be the future of these Helmintkofhila: who now, 

 as it seems to me, show unmistakable evidence of break-down 

 after a long and severe struggle against better adapted forms. 

 This or ultimate extinction are the only alternatives. 



* Brewster, Wm. Bull. Nutt. Oraith. Club, Vol. VI, Oct. 1881, p. 218. 



t Langdon, Frank W. Bull. Nutt. Ornith. Club, Vol V, Oct. 1880, p. 208, plate, iv. 



Auk, 4. Oct. ■ 1887. B. S07-SfO- 



