1152 Eepoht of State Geologist. 



somewhere near the 20th of April. During the last week of April 

 ajid the first three weeks of May it was very common, perhaps more so 

 than any of the other small Thrushes. Specimens were shot May 33, 

 and others were observed as late as the 38th of that month, the date 

 of my departure" (Bulletin Nutt. Orn. Club, Jaoiuary, 1882, p. 19). 

 Prof. B. W. Evermann. has found it common in Vigo County. Prof. 

 W. S. Blatchley noted them at Bloomington, May 1, 1886. Mr. 

 Charles Baj-ber notes it as abundant at Laporte, April 10th to 12th, 

 1892, and Mr. C. E. Aiken informs me that he has found it common 

 in Lake County, May 2, 3 and 4, 1894. Mr. J. G. Parker, Jr., says 

 it is a not uncommon spring and fall migrant neaj Chicago, 111. He 

 has noted it between May 13 (1886) and May 20 (1896), and in Sep- 

 tember. Messrs. L. A. and C. D. Test saw twelve at Lafayette, Sep- 

 tember 4, 1895, and note it May 12, 1892. Mr. Alden M. Hadley 

 took specimens which are in the collection at Earlham College, at 

 Kichmond, September 16 and 19, 1896. Messrs. Diiry and Freeman 

 noted them at Cijicinnati, 0., September 16, 1879, and Dr. E. W. 

 Langdon has observed it in that vicinity "rather common early in 

 October, feeding on the berries of the sour gum" (Journ. Cin. Soc. 

 Nat. Hist., January, 1879, p. 169)'. 



Their habits appear to be substantially the same as the Olive-back's. 

 They frequent the same localities, eat similar food, and are often 

 found together. This species seems to be more solitary, and more 

 retiring in its habits than the other. 



Prof. Forbes found that the food of ten specimens of this Thrush 

 shot in May consisted of five per cent, mollusks, chiefly suceinea and 

 Helix labyrinthica; ninety-three per cent., insects, almost half of 

 these being ants, of \^-hich each bird ate forty-three per cent. Fifteen 

 per cent, of their food was caterpillars: nine per cent., craneflies; 

 eighteen per cent., cohoptera, one-half being aphodidw, and the re- 

 mainder, wire-worms, curculios and plant beetles. Almost none of 

 its food is beneficial elements (Bulletin No. 3, 111. State Lab. N. H., p. 

 130). 



318. (758a). Turdus ustulatus swainsonii (Cab.). 



Olive-backed Thrush. 

 Synonym, Swainson's Thkush. 

 Adult. — Above, uniform olive; ring around eye and light feathers 

 on head, buff; below, throat and upper breast, buff, the sides of the 

 former and all the latter spotted with triangular dark-brown or black- 

 ish spot,s; other lower parts, white, spotted next the breast with ashy 

 and washed on the sides with ashy, sometimes tinged with brownish. 

 Length, 6.35-7.55; winl,^ 3.80-4.10; tail, 2.80-3.10. 



