THE STYLOPS PARASITE. 



45 



The history of Stylops, a beetle allied to Meloe, is no less 

 strange than that of Meloe, and is in some respects still more 

 interesting. On June 18th I captured an Andrena vicina which 

 had been " stylopized." On looking at my capture I saw a pale 

 reddish-brown triangular mark on the bee's abdomen ; this was 

 the flattened head and thorax of a female Stylops (Fig. 39a, posi- 

 tion of the female of Stylops, seen in profile in the abdomen of 

 the bee ; Fig. 39&, the female seen from above. The head and 

 thorax are soldered into a single flattened mass, the baggy hind- 

 body being greatly enlarged like that of the gravid female of the 

 white ant, and consisting of nine segments). 



On carefully drawing out the whole body (PL 1, Fig. 6, as seen 

 from above, and showing the alimentary canal ending in a blind 

 sac; Fig. Ga, side view), which 

 is very extensible, soft and baggy, 

 and examining it under a high 

 power of the microscope, we saw 

 multitudes, at least several hun- 

 dred, of very minute larvae, like 

 particles of dust to the naked 

 eye, issuing in every direction 

 from the body of the parent now 

 torn open in places, though most 

 of them made their exit through 

 an opening on the under side of 

 the head-thorax. The Stylops, 

 being hatched while still in the 

 body of the parent, is therefore 

 viviparous. She probably never 

 lays eg^s. 39 - Female Stylops. 



On the last of April, when the Mezereon was in blossom, I 

 caught the singular looking male (Stylops Children!, Fig. 40 ; a, 

 side view; it is about one-fourth of an inch long), which was 

 as unlike its partner as possible. I laid it under a tumbler, 

 when the delicate insect flew and tumbled about till it died of 

 exhaustion in a few hours. 



It appears, then, that the larvae are hatched during the middle 

 or last of June from eggs fertilized in April. The larvae then 

 crawl out upon the body of the bee, on which they a^e trans- 

 ported to the nest, where they enter, according to Peck's obser- 

 vations, the body of the larva, on whose fatty parts they feed. 



