1927 ] The Slave Raids of Harpagoxenus americanus 
27 
From the foregoing consideration it is clear that H . sublcevis 
shows closer affinities to L. acervorum than does H. americanus . 
This may be correlated with the habits of the two slave-makers. 
Sublcevis has apparently always lived with the host from which 
it was derived and has therefore changed only slightly. On the 
other hand, americanus, adopting new hosts, has diverged to a 
greater extent from the ancestral type. 
In conclusion is given a description of the male of H. amer- 
icanus (Fig. 2.) 
Fig. 2. A, male of Harpagoxenus americanus ; B, head of same. 
