THE PEZOMACHINI OF NORTH AMERICA.! 
By E. H. STRICKLAND. 
The following paper is based mainly on the unnamed collec- 
tion of the genus Pezomachus belonging to the U. S. National 
Museum, which was very kindly lent to me during the spring of 
1911. The bulk of the collection of 317 specimens was com- 
posed of two species, namely: Pezomachus flavocinctus Ashm. 
112 specimens o& and 92, and Pezomachus nigrellus Ashm. 
60 specimens o and 9. ‘The former proved to be the most 
interesting since the hitherto undescribed male yielded a unique 
condition of polymorphism, fully described later in the descrip- 
tion of the species, and in several cases a hyperparasite, Hemzteles 
sp. was bred from the same egg cocoons as individuals of this 
species. Many other already described species of Pezomachus 
were represented as were also 12 apparently new species. J am 
also indebted to Mr. H. L. Viereck of the National Museum for 
a small collection containing one new species, and to Dr. W. E. 
Britton, State Entomologist of Connecticut for a similar collec- 
tion containing two new species of Pezomachus and one new 
Thaumatotypus. 
In working these over I found several cases in which two 
distinct species had received the same name, while some cases 
of wrong generic determination were noticed, which in the 
following pages I have attempted to correct. 
My thanks are due to Mr. C. T. Brues for help received in 
generic determinations. 
The tribe Pezomachint of Ashmead? included all Cryptines 
in which the metathorax is not areolated, or at most with only 
a transverse carina, and consisted of the following genera. 
Thaumatotypus Forster. 
Cremnodes Forster. 
A pterophygus Forster. 
Aptesis Forster. 
Theroscopus Forster. 
Pezomachus Grav. 
Pezolochus Forster. 
Hemimachus Ratz. 
1Contributions from the Entomological Laboratory of the Bussey Institution, 
Harvard University, No. 45. 
2Proc. U. S. Nat. Mus. Vol. XXIII, p. 36 (1900). 
ES 
