AMERICAN ORTHOPTERA. 279 



or posterior portions ; antennae slightly exceeding the body in length. Pronotum 

 sub-triangular in outline, surface moderately polished ; anterior margin narrow 

 and truncate ; posterior margin truncate; lateral margins forming a right angle 

 with the posterior margin and curving gently forward, meeting the anterior 

 margin at a hardly perceptible angle. Tegmina about one and one-third times 

 the length of the pronotum, surface coriaceous; lateral margins parallel, the 

 apical margins emarginate, the apex sutural ; veins not apparent and lost in the 

 general coriaceous mass; anal sulcus evenly curved, apparent only toward the 

 sutural margin, which it joins one-third the length from the apex. Wings not 

 quite equalling the tegmina in length. Abdomen with the lateral margins pro- 

 duced into dentiform processes, strongest posteriorly. Supra-anal plate produced, 

 triangular, tectate ; apex rather narrowly rotundate emarginate. Cerci hastate, 

 depressed, slightly exceeding the supra-anal plate in length. Subgenital plate 

 triangular, median ridge prominent, basal portion somewhat depressed. Anterior 

 femora with ten spines on the distal portion of the anterior lower margin, the 

 apical one very large, the posterior margin with four distally placed spines, two 

 apical, genicular spine as long as, but more slender than, the tibial spines; tibiae 

 about two-thirds the length of the femora ; metatarsi about equal to the terminal 

 tarsal joint in length. Median femora with the anterior margin bearing eight 

 evenly disposed spines, the apical one exceeding the others in length, posterior 

 margin bearing six rather even spines, genicular spine of a character similar to 

 that of the anterior limbs; tibiae slightly shorter than the femora in length; 

 tarsi not quite as long as the tibia?, metatarsi equal to the terminal joint in length. 

 Posterior femora armed with eight spines on the anterior margin, the apical one 

 slightly exceeding the others in length, posterior margin armed with six spines, 

 genicular spine similar in character to that of the other limbs; tibiae exceeding 

 the femora in length by about one-third the length of the latter, very stout and 

 robust; metatarsi about equal to the remaining tarsal joints in length, lower 

 surface dentate, pulvilli apical, arolia large. 



General color mahogany brown ; lateral portions of pronotum and tegmina 

 with a bar of brownish yellow, which on the tegmina is blotched with the gen- 

 eral tint. Top of head, labrum and clypeus dull yellowish. Eyes narrowly 

 margined with yellow. 

 Measurements : 



Length of body, ...... 20. mm. 



Length of pronotum, ..... 7.2 " 



Greatest width of pronotum, . . . 10. " 



Length of tegmina 10.5 " 



Greatest width of tegmina, .... 7.5 " 



Genus PER1PLASETA Burmeister. 

 1838, Periplaneta Burmeister, Handb. d. Eutom., ii, p. 502. Type. — By 

 elimination and selection, Blatta americana Linnaeus. ■ 



* The original species ot Periplaneta are as follows: 

 americana. 

 brunnea. 

 ustulata. 

 Australasix. 

 orientalis, . . Blatta restricted by Latreille, 1802. 



TRANS. AM. ENT. SOC, XXIX. SEPTEMBER. 1903 



