22 BULLETIN 143, UNITED STATES NATIONAL MUSEUM 



This insect is not a free living one but is a brood parasite. It lays its eggs 

 in the nests of bumblebees, where it breeds at the expense of the bumblebee 

 brood. Mutillids of both sexes are ordinarily found in the bumblebee nests 

 in our high mountain regions, especially toward autumn. I think, therefore, 

 that the mutillid female, in order to lay its eggs in the cells of the bee, goes 

 into the hive, but there as a bold invader it is attacked by the bees, and the 

 bees in turn are stung to death — ^possibly bitten to death. A careful investi- 

 gation of the resi^ective organs of the Mutilla may settle the point as to 

 whether it is stinging to death or biting to death. The sting is very long and 

 appears to provide a murderous weapon against the bees. Since the abdomen 

 of the Mutilla is so well armored, the bees can do nothing to it and offer their 

 lives uselessly in combat with the enemy. 



Whether egg laying is really the object of the invasions may be easily deter- 

 mined by an anatomical investigation of the ovaries; if the ripe egg is found 

 in these, then my view will be established. This fact is unimportant except 

 from an academic viewpoint, but the sympathy which we show toward our 

 pets, the bees, on every occasion certainly justifies my curiosity concerning 

 it and impels me to learn the reason for such a tragedy in the apiary. I 

 have observed it now four years, and it has been the despair of our beekeepers 

 many times. 



Schoenfeld's remarks are as follows : 



Whether the mutillid larva occurs as a parasite on the bee maggots, and 

 whether the female mutillid also seeks out the beehives in order to deposit its 

 eggs, can naturally only be learned by careful observation of the hives which 

 are attacked by the mutillids. One can not draw a safe conclusion from the 

 presence of mature eggs in the ovaries of the mutillids which are seized in 

 the brood chambers of the bees. Insects carry their eggs around with them 

 for a very long time, even though these are ripe for deposition, until they find 

 a suitable place in which they are able to deposit them. One finds, for example, 

 living larvae in the abdomen of the blowfly very frequently, which have devel- 

 oped from eggs, because the mother had not found an opportunity to deposit 

 the eggs at the normal time. From the circumstances that only the female, but 

 not the male, of the mutillid is dangerous to beehives one can not with cer- 

 tainty draw the conclusion that the females enter the beehives for the purpose 

 of ovipositing. Both sexes lead a separate life for the most part. AVhile the 

 males usually visit flowers, they are also frequently found on leaves where 

 there are colonies of plant lice, and one usually sees the female running around 

 busily on sandy paths and slopes. It is quite possible that the mutillids only 

 enter the beehives in order to obtain food there. They appear to scorn honey. 

 My specimens, although very hungry, left it untouched ; nor did they know how 

 to begin with a young drone larva which I put before them. When I crushed 

 a delicate nymph they eagerly examined the exuding fluid and licked it up like 

 a dog. 



But what ever induces tliem into the beehive, the calamity which they 

 cause therein according to the description of Herr Schachinger, is great enough 

 to designate them as a mischievous enemy of bees. He surmises that they bite 

 or sting the bees to death. From the anatomical and microscopical investi- 

 gations that I have made of the five si>ecimens submitted to me, I am only able 

 to state that the mouth parts' of these insects appear to be unsuitable for kill- 

 ing, while the stinging apparatus appears to me to be well adapted for that 

 pui-pose. The mandibles although very hard are much too short, so that they 

 would only be able to seize or hold a bee. On the other hand the sting is 



