LEPIDOPTERA OF NEW YORK AND NEIGHBORING STATES 209 



This species is known only from Chambers' meager description. It is probably 

 a synonym of cerasivorella Packard. 



(3) C. occidentis Zeller. 



Alar expanse: 10 mm. 



Locality : Massachusetts. 



Food plant: Prunus serotina. 



Larval case: Brown, cylindrical; upper edge serrate; mouth deflected to 



45 degrees; posterior end triangularly compressed. 



This species is known only from Zeller's description. It is placed in our specific 

 key with fletcherella only tentatively. If the two are one species, as is quite 

 possible, Zeller's name will take precedence over the better known fletcherella. In 

 our lists occidentis is wrongly listed as a synonym of pruniella Clemens. 



(4) C. fletcherella Fernald. 



Alar expanse: 10-12 mm. 



Locality: Northern United States and Canada (June). 

 Food plants : Apple, pear, cherry, hawthorn. 



Larval case (fig. 127a) : Brown; cylindrical; smooth; mouth deflected from 

 45 degrees to 60 degrees; posterior end triangu- 

 larly compressed; 7-8 mm. long. 



This is the economically important " cigar case-bearer " on apple, and is easily 

 distinguished from other gray-brown, unicolorous species by its yellowish head. 

 It is probably a synonym of occidentis Zeller, but this can only be decided by 

 further and more extensive rearings. Zeller describes the larval case of occidentis 

 as serrate above. All cases of fletcherella in the United States National Museum 

 have the upper edge smooth. 



(5) C. laricella Hlibner. (Fig. 124). 



Alar expanse: 9-10 mm. 



Locality: northeastern United States. 



Food plant : Larch. 



Larval case: Gray, with a yellowish or brownish patch on the outer side 

 extending from the mouth and formed by a part of the 

 leaf fiber woven into the case; mouth deflected from 45 

 degrees to 60 degrees; posterior end triangularly com- 

 pressed; 5 mm. long. 



This species is commonly known as the " larch case-bearer," and often does 

 considerable damage to the trees. 



(6) C. unicolorella Chambers. 



Alar expanse: 8-9 mm. 



Locality: Eastern United States (June). 



Food plant: Seeds of Juncus. 



Larval case : Dirty gray, ornamented with many small f rass pellets ; 

 stout; cylindrical; mouth deflected to 90 degrees; posterior 

 end broad, pyramidal, triangularly compressed; 4.5-5 mm. 

 long. 



(7) C. pruniella Clemens. 



Alar expanse: 12.5-13 mm. 



Localities: Pennsylvania; Ohio. (June). 



Food plant: Prunus serotina. 



Larval case: A double affair, composed of a small curved, silken first 

 case, inserted into a later one cut from the serrate edge 

 of the mined leaf, thus resembling a pistol butt projecting 

 from a holster (in the spring often losing the silken pos- 

 terior part); mouth slightly deflected; posterior end 

 rounded and flatly compressed; 5-6 mm. long. 



