MORGAN HEBARD 6l 



Neoblattella chagrensis**'^ new species (Plate III, figure 14.) 



This species belongs to the second division of the Impar Grf)up, 

 having, in the male, a simple type of subgenital plate, with simple 

 cylindrical styles and lacking accessory specialized appendages. 

 The concealed genitalia, however, show high specialization, and in 

 several closely related tropical North American species before us,*^ 

 aside from differences in size, pronotal proportions and develop- 

 ment of tegmina and wings, the concealed genitalia alone afford 

 conspicuous diagnostic characters in the very distinctive develop- 

 ment found in each. The very remarkable fact is that, in all of 

 these species, the male subgenital plate and styles are the same in 

 form and proportions, whereas in all the other very numerous 

 species of the genus before us, the male subgenital plate and 

 styles, in every case, show remarkable and constant diftcrential 

 characters. 



Only two species of the Impar Group, having the distal tegminal 

 cross-veinlets strikingly darkened, have been described; one of 

 these, brunneriana (Saussure)," from Mexico,***^ the other, albida 

 (Saussure),'^^ from Colombia. Unfortunately, though in general 



*5 In reference to the type locality of the species, situated in the Chagrcs River 

 drainage. 



*^ These other species are, apparently, yet undescribed. 

 "Neoblattella brunneriana (Saussure) 



1868. Blatta brunneriana Saussure, Rev. et Mag. de Zool., 2e ser., xx, p. 78. [ 9 ; 

 [Cordillera Oriental], Mexico.] 



1870. Blatta brunneriana Saussure, Miss. Sci. Mex., Rech. Zool., Orth., p. 32, pi. i, fig. 

 20. (More complete discussion of type.) 



Type, ex Saussure: length of body, [i] 2; length of liody and tegmen, [i] 6; length of 

 pronotum, 3; width of pronotum, 4 mm. 



** We find that our diagnosis given for the previously undescribed male of brunneriana 

 (Ent. News, xxvii, p. 159, footnote 3, (1916)), unfortunately does not apply to that 

 species, but to a related, distinctive, undescribed species. The material then supposed 

 to represent brunneriana (Ent. News, x.wii, p. 159, footnote i) includes several 

 undescribed species of the Impar Group. 



»3 Neoblattella albida (Saussure) 



1869. Blatta albida Saussure, Rev. et Mag. de Zool., 2e ser., xxi, p. no. [cf ; Bogota, 

 [Colombia].] 



•1870. Blatta albida Saussure, Miss. Sci. Mex., Rech. Zool., Orth.. p. 37. (More com- 

 plete discussion of type.) 



Type, ex Saussure: length of body, 10.2; length of tegmen, 12.5; length of pronotum, 

 2.6; width of pronotum, 3.8 mm. 



MEM. AM, ENT. SOC, 4. 



