in honour of Mr. Thomas Nuttall, who disco- 

 vered it. 



Although this insect certainly belongs to this 

 genus, yet the proportional length of the second 

 and third joints of the antennae, is somewhat 

 similar to that of the genus Zonitis, as defined 

 by Latreille in the Regne Animal. In common 

 with several other American species, the antennae 

 increase a little in thickness towards the tip, but 

 are much shorter than in Zonitis. These cha- 

 racters, combined with the form of the terminal 

 joint, seem to prove a close alliance with the 

 genus Mylabris, but the antennae are not ar- 

 quated at tip, and are of a more considerable 

 length; the habit also differs, the form of the 

 body being more elongated. The species, then, 

 possessing the form of antennae above noted, 

 seem to have the habit of L\tta, combined with 

 a form of antennae allied to that of Mylabris. 



They cannot be referred to Zonitis, as the 

 palpi are not filiform, and the habit does not 

 agree. 



The nuttallii seems to be limited to the west- 

 ern region. In company with Major Long, I 

 observed it, for the first time, near the base of 

 the Rocky Mountains. A very numerous flock 

 had there taken possession of the few diminutive 



PLATE III. 



