G86 BOSTON JOURNAL 



It resembles the malacus, and requires the additional descrip- 

 tion I have now given, to be distinguished from it. [228] I 

 have found this species in Indiana, Missouri and the North-west 

 Territory. The " acute angle " of the metathorax is prominent 

 spiniform. 



4. I. OTiosus nob. (ibid, p. 69.) — Occurs in Indiana and 

 North-west Territory. 



It resesemblesitn?yasc;'a/om<snob. Amer. Entoni. vol. ii. [ante, 

 1, 48,] but is rather smaller, the annulation of the antennae is 

 differently situated, and it has two abbreviated white lines on 

 the middle of the thorax. 



5. I BREViciNCTOR nob. Amer. Entom. pi. 22. — Terminal 

 segment of the tergum with a large, white, rounded spot. 



6. I. PARATA nob. Contr. Macl. Lye. p. 68. — The following 

 is a description of the opposite sex, and of some of its varieties. 



Body black : head with yellow orbits, mouth and hypos toma : 

 antennae beneath dull honey -yellow ; basal joint beneath yellow : 

 thorax with two small abbreviated lines on the disk, line before 

 the wings approaching before, and wing-scale yellow : scutel 

 yellow : wings slightly tinged with fuliginous : nervures pale 

 brownish ; stigma dull honey-yellow ; second cubital cellule pen- 

 tagonal, the two recurrent nervures with a short process near their 

 middles : metathorax with a dilated spot each side, often con- 

 fluent, and a small line under the scutel : tergum with four di- 

 lated yellow bands : feet yellow ; posterior thighs, excepting their 

 base and their trochanters, black ; posterior tibiae at tip black. 



Length over three-fifths of an inch. 



Var. *• Tergum with but two bands. 



Var. /i. Metathorax immaculate behind. 



Var. y. Bands of the tergum contracted in the middle. 



Var. S. Short lines of the thorax confluent, so as to form a 

 lunate spot. [229] 



Var. s. Short lines of the thorax obsolete. 



A very common species. I have taken it in Missouri, Indiana, 

 Pennsylvania and N. W. Territory. 



7. I. COMPTUS. — Black ; tergum with a yellow band on each 



segment. 



Inhabits United States. 



[Vol. I. 



