302 Observations on the 



tail is nearly obsolete, and the legs (from their great length), 

 evidently show we have reached a group of cursorial or ambulating 

 birds, who rarely, if ever, frequent trees. These I shall call 

 Urotomus. Finally, there seems to be another group, wherein 

 the tail is again developed ; the tarsi are proportionably long, but 

 more robust ; and the whole habit shows a much greater analogy 

 to the Meruladce, than any of the foregoing types : these birds I 

 ^ l shall, for the present, consider as forming the genus Drymophila. 

 Whether they should precede or follow Urotomus, in our advance 

 towards the Myothera? of Uliger ; or whether they will partially 

 bring us back (by a circular disposition of the other types) to 

 Thamnophilus, are questions which must be decided by others, 

 whose cabinets are better stored with materials for ascertaining 

 these points. At all events, either Urotomus or Drymophila will 

 conduct us very close to Tardus Colma, the bird which forms the 

 original type of Illiger's genus Myothera. 



Having now enumerated all the South American types I have 

 seen which intervene between Thamnophilus and Myothera, I must 

 postpone the investigation of such other kindred groups as may be 

 found to inhabit Africa, India, or Australasia. The Indian Myothera; 

 of M. Temminck seem to differ so little from my group Formicivora, 

 that they may, possibly, be united together ; while the interval 

 between the long-tailed Drymophilce and the true Myotherw, may 

 perhaps be filled up either by American species I have not yet 

 seen, or by certain African birds, only known to me by the figures 

 of Le Vaillant. But this is conjecture, and indeed belongs not 

 to our present inquiry, which is more to ascertain what groups 

 really constitute the circle of Laniadw, than to trace their ramifi- 

 cations into other tribes. In the two we have already investigated, 

 namely, Lanianw and Thamnophilinaz, there evidently seems a 

 double affinity : one, by which they themselves are united, and 

 which may be termed a family affinity ; and another, by which 

 they branch off, by different routes, into the neighbouring family 

 of Meruladw, and may therefore be called collateral. 



These two affinities are particularly observable among the 

 Thamnophilinw. Whether the different changes of form, by which 

 we see these transitions are effected, be called genera, subgenera, 



