146 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.43. 



the scutellum from tlie scutum; the one calcarium of the anterior 

 tibiae, the loss of notauh, the loss of the proepimeron; and they are 

 more like them in venation than other Chalastogastra. The loss of 

 cerci would place them near Tremicinse. It may be that they were 

 derived from the Tremicinae, but they may easily be separated from 

 this group by the characters found below. From the standpoint of 

 the wings MacGillivray (1906, p. 646) said: 



So far as their wings are concerned the presence of the second anal cell in the front 

 wings is the only structure that would place the genus Oryssus in the superfamily 

 Tenthredinoidea.i 



Ashmead (1898, p. 177) expressed the opinion that Oryssidse were 

 apparently, 



the stem from whence some of the parasitic Hymenoptera originated, i. e., the Mega- 

 lyridse, Stephanidae, etc. 



CLASSIFICATION. 



The present paper being of preliminary nature, it is only possible 

 at present to point out certain characters which have not been used 

 heretofore in systematic work on these insects, with the hope that 

 other workers will endeavor to make use of them. The prepectus is 

 well defined in Oplirynopus, while it is poorly defined in Oryssus and 

 Chalinus. This character may prove useful to separate genera. The 

 use of the number and type of the facial carinse may not be the most 

 natural classification, but it is sllo^^m on page 142 that it goes hand in 

 hand with the assumed southern extension of the group. The denta- 

 tion of the hind tibisB ma}^ be of some value. Specific characters 

 may be found on the so-called clypeus, the relation of antennal joints, 

 the shape of the hypopygidium, and other characters mentioned in 

 the following table. Harrington (1886-7) was of the opinion that 

 all the American species were the same and that certain well-marked 

 color forms existed. To adopt Harrington's synonymy would mean 

 that the characters found on the antennae, clypeus, and others are 

 not of specific value. Without more conclusive evidence it is much 

 better to treat these as distinct. It may be, however, that Harring- 

 ton had before him only one species and that this species varied as 

 his material indicated. Bradley (1901, p. 317) expressed the opinion 

 that the color represented constant specific differences, and Konow 

 (19056, p. (354) 178) went even further than Bradley in recognizing 

 qffinis Harris. 



Superfamily ORYSSOIDEA. 



Oryssoidea Rohwer, Proc. Ent. Soc. Wash., vol. 13, No. 4, 1911, p. 217. 



Distinguishing characters. — Pronotum with the posterior margin 

 strongly curved; mesoscutum extending much beyond the anterior 

 margin of the tegulae; abdomen with eight sternites and eight tergites; 



> MacGillivray uses the term "Tenthredinoidea" in the sense of "Chalastogastra" of the author. 



