1912.] NATURAL SCIENCES OF PHILADELPHIA. 97 



specimens, one of each sex, if both sexes were available. It is 

 consequently evident that, among the species at present under 

 consideration, a great number will be found already limited to a 

 single type, and the present limitations of the others consist merely 

 in determining which sex should be selected as single type. There 

 is but one case, that of Homceogamia subdiaphana mohavensis, where, 

 in the original description, the limitation was accidentally over- 

 looked. The present paper falls naturally into two portions. The 

 first of these treats those species which have been described by the 

 senior author; there are forty-five of these, of which twenty-four are 

 located in the Academy of Natural Sciences of Philadelphia, eleven 

 in the Collection of the University of Kansas, six in the Kebard 

 Collection and two each in the United States National Museum 

 and the Museum of the Brooklyn Institute of Arts and Sciences. 

 The second portion treats those species described jointly by the 

 authors of the present paper; there are thirty-eight of these, thirty- 

 four in the Hebard Collection, three in the Academy of Natural 

 Sciences of Philadelphia and one in the United States National 

 Museum. The nomenclature given will be that of the original 

 description, as these papers are not intended to be at all revisionary; 

 the names generally conceded to be absolute synonyms, however, 

 have been omitted. 



Part One — Species of North American Orthoptera described 



by James A. G. Rehn. 



ISCHNOPTERA JOHNSONI. 



Ent, News, Vol. XIV, p. 234, 1903. 



Based on a unique male from St. Augustine, Florida; C. W. 

 Johnson; A. N. S. P. Collection. 



Homceogamia erratica. 



Proc. Acad. Nat. Sci. Phila., 1903, p. 187. 



Described from one male from Prescott, Arizona, June 10, 1902; 

 Oslar; A. N. S. P. Collection. 



Chorisoneura plocea. 



Ent, News, Vol. XV, p. 164, 1904. 



Described from a unique female from the coast of South Carolina 

 [probably near Charleston] ; 24 Hebard Collection. 



21 Brackets are used in the present paper wherever additional data is given to 

 that contained in the original description. 



7 



