250 BULLETIN 195, UNITED STATES NATIONAL MUSEUM 



from the south the males sing almost constantly." The songs at this 

 time often average about 25 per minute, but during nest building the 

 songs are less numerous and the intervals between singing periods 

 become longer. 



"The display of the male is quite simple but interesting. "When the 

 female is near he will take up his station a foot or two above her, fluflf 

 out his breast feathers and under tail coverts, and jauntily cock his tail 

 over his back so that it almost touches. He now resembles a tiny ball 

 of feathers perched among the reeds. As he becomes more animated he 

 beats his partially folded wings up and down rapidly and sways his 

 head dizzily from side to side. The female probably will fail to notice 

 him, or at least she will not indicate any interest, and, after pursuing 

 her and displaying for several minutes, he will burst into song and fly 

 to another portion of the territory." 



The sexual organs of the male are well developed when he arrives, 

 but those of the female are not, so that she has to avoid him until she is 

 ready. Dr. Welter continues : 



During the period of nest construction she reaches the height of her development 

 and is ready for the mating act. When the male approaches her at this time, 

 singing, she climbs up a cat-tail stalk and gives the trill which has already been 

 described. Then she beats her wings rapidly, points her bill toward the zenith, 

 and places her tail well over her back. The male goes through the courtship 

 display previously described. At the proper time he climbs upon the back of his 

 mate, beats his wings rapidly as the cloacae come in contact and copulation is 

 completed. The whole procedure takes but a few seconds. Both remain in the 

 immediate vicinity for a short time, the male with feathers fluffed out and tail up, 

 the female quiet and demure. 



It is usually the male who tries to induce the female into copulation but on one 

 occasion the female was observed going through the behavior leading to the mating 

 act to entice the male. In this instance the act had been completed 25 minutes 

 previously. The male, not giving the proper response, was chased by the female 

 among the cat-tails and it is not known whether she was successful or not. 



Dr. Welter believes that the male is "essentially polygamous while 

 the female is not." Several of the territories were inhabited by one 

 male and two females, and in one doubtful case it was thought that a 

 male had three mates. There was another doubtful case of polyandry, 

 where a female had no regular mate, and her nest was placed between 

 the territories of two mated males. 



Nesting. — The prairie marsh wren nests in wet marshes, where the 

 water is from a few inches to 2 or 3 feet deep, along the banks of tidal 

 rivers where the water is brackish (in Massachusetts), along sluggish 

 inland streams, around the shores of ponds, and in inland marshes or 

 sloughs. It seems to prefer to build its nest in the narrowleaf cattail 

 {Typha angitstifolia) , seldom using the broadleaf species {T. lati- 

 folia). Early in the season, before the green flags have grown to suf- 

 ficient height, I have found the nest in some thick bunch of the dead 

 flags of the previous season, but the new green flags are much pre- 



