XXxii, '21] ENTOMOLOGICAL NEWS 241 



Described from the type specimen only, which is a female, 

 collected by the writer, Feb. 14, 1921, at Takoma I 'ark. Mary- 

 land, in decaying leaves. This female was taken from a small 

 pocket on the side of a hill only a few rods from mv home. 

 The specimen is mounted in balsam with the legs extended and 

 is in fine condition, llecause of the present lack of the proper 

 analysis of specific characters in the Protura. it appears 

 desirable to have included in this description only a single 

 individual. After a more complete studv has been made auto- 

 types can be designated. 



The Curious Mating Habit of Megarhyssa atrata (Fab.) Hymen.: 



Ichneumonoidea). 



The discovery of the curious mating habit of Mcfiarliyssa atrata 

 throws some light on the reason for the previous emergence of the 

 males. Very little seems to have been recorded concerning the mating 

 habits of the Ichneumonoids. It is the rule among these insects that the 

 males emerge before the females, especially those parasitic on w<>'! 

 boring species. In this respect ]\Ic</arhyssa is a striking example. 



During the early season before the females of Megarhyssa have 

 appeared in numbers, groups of males may be observed congregating 

 at a certain point on a dead tree that is also a host for Trcmc.v coluinba 



( Linnaeus ). 



On May 9, 1921, at Harrisburg, Pa., the writer visited a dead standing 

 beech, which had been the host for Trcnu'.v culiiinhit for several years, 

 and in which two and possibly three species of ]f('<inrhyssa were found 

 ovipositing during preceding summers. On this date several groups of 

 from six to ten males of Mcf/arliyssn were found. A closer examina- 

 tion showed that in each group one male had the whole of his abdomen 

 inserted into the tree, through a hole either chewed through the surface 

 by the emerging female, or from the outside by the male. This hole 

 was only large enough to admit the abdomen of the male, although the 

 other males present were attempting to insert their abdomens. 



The tree was then cut into at this point, and the female of Mt'tiarhyssa 

 ulrutu was found mating with this male. The blow from the axe dis- 

 turbed , -the pair and separated them before definite observations on the 

 j ' cess could he made; but it was apparent that the females of 1 /,</<"'- 

 /M'.v.vu arc tiTtili/ed before- they emerge. The males probably are 

 attracted by scent, and congregate at the point from which she will 

 merge. 



S. A. Kohwer states* that Mc;nirh yss.i atrata (Fab.) had not been 

 definitely associated with its host, it was tound in this tree as a para- 

 site of Tremex columba (I..), as are all but one of the species of 

 Megarhyssa. A. I'.. ('IIAMTKAIX. lYnnsyhai'i.i I'.nreau of I'lant Indus- 

 try, ! larrisbnrg, I ';>. 



* I'roc. U. S. Nat Museum, Vol. 57, No. -VM7, p. 4_ >n . 1"_>(>. 



