IxYi INTRODUCTION, 



Genus Stellula, Gould. 



(dim. of Stella?) 

 Generic characters. 



Male, — Bill longer than the head, straight and pointed; wings moderately long and sickle-shaped; first pri- 

 mary rigid ; tail short and truncate ; feet small ; claws diminutive and curved. 



The starry throat-mark of this bird would appear to indicate that it should be associated with the members of 

 the next genus, Calothorax ; but on an examination of the tail we find it to be short and truncate, and that con- 

 sequently the bird is of a very different form. 



At present but one species of this form has been discovered ; and this ranges very far north, not only over 

 the high lands of Mexico, but even enters California, as is shown by specimens having been sent to me from 

 thence by Dr. Baird of Washington, and Mr. Bridges of California. 



161. Stellula Calliope. 



Calothorax Calliope, Gould Vol. III. PL 142. 



Habitat. The table lands of Northern Mexico and California. 



The type of the 



Genus Calothorax, G. R. Gray^ 



is the well-known Mexican Star, C. cyanopogon, which, together with the new species discovered by M. Salle, and 

 named by me C. pulcher, are all that are known of this pecuhar form. Both these birds are natives of Mexico- 

 one inhabiting the table lands, the other the more southern and hotter districts. Both have very singularly formed 

 tails — the outer feather being shorter than the next, and the four central ones so abbreviated as to be almost hidden 

 by the coverts. When the males display their luminous gorgets, they must appear truly beautiful. The females 

 possess none of this fine colouring, but, on the contrary, are very plainly attired. 



162. Calothorax cyanopogon ............. Vol. III. PL 143. 



Trochilus cyanopogon, Swains. Birds of Brazil, pi. 77. 



coniscus, Licht. Preis-Verz. Mexican. Thier. v. Deppe & Schiede (Sept. 1830) No. 34, 35. 



Habitat. The table land of Northern Mexico. 



163. Calothorax pulcher, Gould ........... Vol. III. PL 144. 



Habitat. Oaxaca in Southern Mexico. 



It has always appeared to me that the well-known Calothorax Mulsanti and C. Heliodori might very properly 

 be separated into a distinct genus ; and this I have accordingly done. With these must be associated the species 

 to which I have given the name of C. decoratus, and, I think, the singular httle C. micrurus. They are all from the 

 Andes, and are among the most diminutive of the Trochilidas. Their structure would lead one to suspect that their 

 wings are capable of vei^y rapid motion, that organ being so small that it must be moved with increased rapidity 

 to enable the bird to sustain itself when poising before a flower. 



Genus Acestrura, Gould. 



(^oiKeaTpa, acus, et ovpa, cauda.) 

 Generic characters. 



Male.— Bill longer than the head, cyhndrical, and very shghtly arched ; two centre tail-feathers extremely 

 small, the two outer ones filamentous and shorter than the third ; wings diminutive ; tarsi clothed ; feet small ; 

 gorget luminous. 



Female — Unadorned. 



164. Acestrura Mulsanti. 



Calothorax Mulsanti ........,,,,, Vol. III. PL 145. 



Lucifer Mulsanti, Reichenb. Troch. Enum. p. 10. 

 Trochilus filicaudus, Licht. in Mus. Berol. 



Chaetocercus Mulsanti. Cab. et Hein. Mus. Hein. Theil iii. p. 60. 

 Habitat. The temperate regions of the Andes, from Bogota to Quito. 



I observe that specimens from the former locahty are smaller than those from the latter. Mr. Fraser found 

 this bird at Pallatanga and Puellaro in Ecuador. 



