MICRASTUE.— HEEPETOTHEEES. Ill 



Nicaragua, Matagalpa, La Libertad, Santo Domingo, Eio Coco (Richardson), Lake 

 Managua {Mm. Brit), Rio Escondido {Richmond i°) ; Costa Eica {v. Frantzius " , 

 Gabb ^), Monte Redondo {Zeledon % Estrella, Jimenez, Irazu, Talamanca, Pozo del 

 Pital, Carillo {Underwood); Panama, Volcan da Chiriqui, Calovevora^, Calobre 

 {E. ArcS), Lion Hill {M'Leannan ^*). — South America, Colombia, Ecuador ^. 



M. guerilla belongs to the smaller section of the genus Micrastur, in which all the 

 species are characterized by a closely-barred under surface. It differs from its South- 

 American allies in having the abdomen barred like the breast. 



Though procured in nearly every State within our limits, and of most frequent 

 occurrence in Costa Rica, this species appears to be nowhere common. 



We have no record of its food or habits. 



Group B. 



Subfam. HERPETOTHERIN^. 



This subfamily contains the single genus Herpetotheres, which again consists of one 

 species only, H. cachinnans, a bird of wide range in South and Central America. 

 Mr. Ridgway, in his ' Outlines of a Natural Arrangement of the Falconidae,' makes 

 Herpetotheres the representative of one of his four groups of Falconinse, the Herpeto- 

 therinse of the ' Nomenclator Avium Neotropicalium.' He gives it the following 

 characters, which, taken together, separate it from the other groups of the same main 

 section of the family : — " Posterior toe elongated, almost equal to the lateral pair. Tarsi 

 and toes covered uniformly with thin, rough, imbricated scales. Tomia without tooth or 

 notch. Nostrils as in the Falcones and Polybori. Superciliary process of the lachrymal 

 elongated, very broad, reaching nearly across the orbit. Posterior margin of the 

 sternum nearly even, entire, and without foramina. Primaries as in Polybori and 

 Micrastures." Mr. Ridgway also extracts some characters of the pterylography of 

 Herpetotheres and Micrastur from Nitzsch's work, by which these groups may be 

 distinguished. Herpetotheres has distinct eyelashes ; the lumbar tract is present; the 

 dorsal portion of the spinal tract is sparsely feathered to the caudal pit, thence 

 diminished and continued as a narrow band along the caudal vertebree to the oil-gland. 



HERPETOTHERES. 



Herpetotheres, Vieillot, N. Diet. d'Hist. N. xviii. p. 317 (1817) ; Sharpe, Cat. Birds Brit. Mus. i. 

 p. 277. 

 This genus bears a strong outward resemblance to the Serpent-Eagles {Circaetus, 

 Spilornis, &c.) of the Old World, especially as regards the coarse reticulation of the 

 tarsus. Like the species of the above-named genera, Herpetotheres feeds upon reptiles 

 and grasshoppers, and is arboreal in its habits. 



