84 Mr. Swainson's descriptions 



Art. XI. The characters and descriptions of several Birds 

 belonging to the genus Thamnophiliis. By William 

 SwAiNsoN, Esq. F.R. Sf L.S. Sec. 



Before entering upon the immediate object of this paper, I 

 feel it necessary to acquaint the readers of the Zoological Journal, 

 that I am prevented from oflFering to them in this, or perhaps the 

 next number, the conclusion of my observations on the family of 

 Laniadce. Several new forms have come under my examination, 

 and with others, scattered in private collections, I have yet but an 

 imperfect acquaintance ; these may probably throw some addi- 

 tional light upon the imperfect attempt I have made to illustrate 

 this intricate subject. 



In the mean time, having the materials before me, I hope to 

 interest our ornithologists by the characters and descriptions of 

 several birds belonging to the American genus Tham7iophilus, most 

 of which I presume to be undescribed. I aaj presmne, because 

 everyone who has directed his attention to the investigation of ex- 

 otic birds, must be aware of the difficulty, not to say the impossibi- 

 lity, in many cases, of ascertaining whether a species is or is not re- 

 corded. These difficulties, as may be expected, frequently lead to 

 unavoidable mistakes, particularly among our own zoologists, who 

 have to contend against the many and great disadvantages arising 

 from the want of zoological institutions in this country. How, it 

 may be asked, are we to institute comparisons between subjects 

 only to be found in the well-stored museums of the continent ? 

 or how can it be expected we should be intimate with the scientific 

 works there published, when they are not to be found in our 

 public libraries ? The private fortune of few, if any, of those who 

 devote themselves to the science, is adequate to supply these 

 numerous and expensive publications. Under such disadvantages, 

 accuracy on this head becomes impossible. A shade of doubt 

 and uncertainty must be thrown upon every question, the bearings 

 of which are not immediately within our cognizance. And al- 

 though this may impress many persons with an idea that our opi- 



