rOWA ACADEMY OF SCIENCES. 235 



In working over the additional material accumulated, and in 

 rearranging the Orthopterous collection of the Iowa Agricul- 

 tural college during the early part of the year several addi- 

 tional species were found; these, with some material collected 

 in Lyon and Mahaska counties several years ago, together 

 with the collecting of the present season at Ames, have fur- 

 nished the basis for an addition of some 30 species to the list 

 published by Professor Osborn in the proceedings of this 

 academy for 1891. 



Owing to the fact that there has been considerable revision 

 in nomenclature and synonomy since the publication of the 

 former list, thus rendering necessary a number of changes, 

 and further that a majority of the species would be included in 

 the notes, it has been thought best to make the list of species 

 complete, although in a number of cases nothing additional can 

 be given. 



The arrangement of families in the list is purely arbitrary, 

 for as yet there seems to be no satisfactory arrangement based 

 upon philogenetic deductions. Within the families the ordi- 

 nary arrangement has been adopted except where there has 

 been recently suggested changes. In the groups Tettigingo 

 and Tryxalinas, Prof. A. P. Morse's recent revision has been 

 followed and in the Tettiginso he has kindly verified all the 

 determinations. To Professor Scudder I am indebted for the 

 determination of the Ceuthophilus listed. While to Professor 

 Lawrence Bruner I am under obligations for the determination 

 of a number of species and the verification of the greater portion 

 of the remainder of the list. 



ORDER ORTHOPTERA. 



Fam. FORFicuLiD.E— Earwigs. 

 Labia minor Linn, A few specimens taken each year. 



Fam. BLATTID.E — Cockroaches 

 Ectobia germanica Steph. Common in stores and houses in 

 towns. 



Ischnoptera unicolor Scudd. Occasionally taken at Ames. 

 Specimens were found abundantly in the timber around 

 Oskaloosa in June. 



Ischnoptera 'pennsylvanica DeGeer. Abundant in the timber 

 along the larger streams. Adults during early summer, disap- 

 pearing by the middle of July. 



Periplaneta oricntali-s Linn. This introduced species, which 

 was formerly confined to a few of the larger cities, has spread 

 5 



