ECONOMIC RELATIONS OF OUR BIRDS. 
605 
41. Dendrceca Pennsylvanica (Linn.), Bd. CHESTNUT-SIDED WARBLER. 
Group I. Class a. 
It has been my experience to find this Warbler barely common. It is a sum¬ 
mer resident from Berlin northward in Central Wisconsin. Dr. Iloy speaks of • 
it as breeding in abundance at Racine, but during three summers’ collecting in 
Jefferson county it was not my fortune to meet with it except during the migra¬ 
tions, and even then, it has been among the rarest of this genus with which I 
have met. During the breeding season, it has been Mr. Allen’s experience to 
find this bird usually in low woods and swampy thickets, nesting in bushes. Mr. 
Ridgway found it breeding in oak openings and among the prairie thickets of 
Southern Illinois. Dr. Hoy states that it jDrefers localities with a dense under¬ 
brush, especially hazel, thinly covered with trees. While at Waupaca, between 
July 30th and 34th, I met two pairs of these birds busily feeding their broods 
high among the tops of deep, heavy maple woods, and another similarly engaged 
on the borders of a tamarack swamp. At Berlin during the month of June I 
observed it in similar situations. It usually lays four eggs in a nest placed in 
the upright forks of a low bush. The Cowbird sometimes deposits its eggs in 
the nests of this species. 
Food: Of eleven specimens examined, one had eaten three ants; two, four 
caterpillars; one, a tipulid; five, twelve beetles; one, fifteen plant-lice; and one, 
a small grasshopper. 
Among the caterpillars were two geometers, marked above, on a yellow ground, 
with numerous fine wavy black lines. These were very abundant at Berlin in 
June of 1874, feeding upon the red, white and burr oaks, the hazel, hickory, iduin, 
chei’ry, apple, pear and currant. 
Insects (Wils.). Flies and other Insects (De Kay). Canker-worms (Maynard). 
4^. Dendrceca maculosa (Gm.), Bd. BLACK-AND-YELLOW WARBLER, 
Group I. Class a. 
This elegant little Warbler is nearly as abundant as the Yellow-rump, and, like 
it, a migrant. Its spring migration occurs between the 5th and 38th of May. 
Between the 3d and 37th of September it returns again to the south. During 
these movements it frequents groves and the borders of woodlands, where it 
gleans among the branches and foliage after the manner of the Creepers and 
Flycatchers. It is also to be seen in osier and alder thickets, in tamarack 
swamps and in the clumps of willows that grow on wet marshes. 
Food: Of seventeen specimens examined, three had eaten four hymenoptera, 
among which were two ants; one, one moth; six, seventeen caterpillars; six, 
fifteen diptera; six, twelve beetles; and one, two larvae. Two tipulids were rep¬ 
resented among the diptera. 
43. Dendrceca tigrina (Gm.), Bd. CAPE MAY WARBLER. Group I. 
Class a. 
This Warbler, once so rare as to have escaped entirely the notice of both Audu¬ 
bon and Nuttall, is apparently becoming not uncommon. Mr. Nelson sa 5 "sof it: 
“ Very common migrant. May 7th to 35tli, a)id September 5th to 30th. In spring, 
found almost exclusively in the tops of trees: in autumn, found in large numbers 
along roadsides, borders of woods and fields in company witli D. pah)iarnm, from 
which it is with difficulty distinguished at gun-shot, so closely alike are their 
habits and movements at this season.” 
