OF WASHINGTON, VOLUME XV, 1913 149 



TENTHREDO ARCUATUS (Foerster). 



On August 8, 1909, at Sonnenberg, Lucerne, Switzerland, I had 

 the opportunity to make the following observations on the feeding 

 habits of an adult which belonged to this species. This adult had 

 only one antenna, but as far as could be observed behaved in a per- 

 fectly normal manner, and was so docile that it could be observed 

 under a half inch lens. This female would fall, alighting heavily 

 on the head of one of the common Umbellifers and. due to the mo- 

 mentum of the flight, would fall beneath the head of the Umbelli- 

 f'T. After recovering itself and righting itself on the flower, it 

 would bite a stamen off near its base and fall beneath the crown 

 of flowers holding itself downward by the four posterior legs. In 

 this position it proceeded to devour an entire stamen, using the 

 maxillary palpi, mandibles and labrum, but the labial palpi did 

 not move. After the entire stamen had been devoured the saw- 

 fly would repeat the operation until it had completely devoured 

 four stamens. After devouring four stamens it walked over the 

 head of the flower and by use of the palpi obtained the small 

 drops of liquid adhering to the base of the receptacle. After visit- 

 ing all the flowers on the head, the insect took flight. To make 

 sure of the species it was captured before it had the opportunity 

 to alight on another flower. The species of Umbellifer was not 

 determined. 



In commenting on this species in the Entomologist for Febru- 

 ary, 1913, Morley states that he has seen it chase flies and has 

 known of one female found masticating a female Empria pcnnipes. 



TWO ABNORMALLY DEVELOPED SAWFLIES. 



BY S. A. ROHWER, Bureau of Entomology. 



Although the sawflies often have abnormal venation, it is very 

 >eldom that a sawfly with abnormal body characters is ever col- 

 lected. As far as I am able to learn only seven gynandromor- 

 phic sawflies have been reported upon. In view of the fact of the 

 usual stability in the bodies of sawflies the following notes may be 

 interesting. 



XENAPATES TERMINALIS (Say). 



On May 13, 1911, along with other sawflies collected at East 

 Falls Church, Virginia, an abnormal female of this species was 

 collected. The abnormality occurs in the abdomen which dm- 

 not have the gonapophyses developed except slightly, and the nates 

 are abnormal. The cerci are normal as is the rest of the insect. 

 The abnormal development of the eighth ventral and the entire 



