segments of the abdomen in Prosopis. Ill 



hesitate to divide such a well-known and easily recog- 

 nised genus, especially as I have failed to find any 

 corresponding characters in the female. 



I have not here touched upon the peculiarities 

 exhibited in the final segment or genital armature, 

 although they are equally distinct and characteristic in 

 each, for I hope to describe and figure them shortly in 

 the second part of my ' Synopsis of the British Hyme- 

 noptera.' 



I have also so far sought in vain for any corresponding 

 features in the terminal segments of the female, but I 

 have only dried specimens to work from, and hope, with 

 freshly-killed examples, to be able to pursue my investi- 

 gations more satisfactorily. 



Explanation of Plate VI. 



1. p. cornuta, Sm. j ' 



2. P. dilatata, Kirb. 



3. P. comtnunis, Nyl. 



4. P. hyalinata, Sm. 



5. P. confusa, Nyl. 



6. P. signata, Panz. 



7. P. ptitictulatissima, Sm. do 



8. P. pictipes, Nyl, 



9. P. hrevicornis, Nyl. 



Note. — Since reading the above, Mr. Fitch has called 

 my attention to two interesting papers bearing on this 

 subject, one by Dr. H. Eeinhard (Berl. Ent. Zeit. 1865, 

 p. 187), and the other by Dr. H. Schaum (Ann. Mag. Nat. 

 Hist., March, 1863). The latter author, however, only 

 finds thirteen segments in the larvae of Hymenoptera, 

 including the head, and on this ground, admitting as he 

 does the transfer of the 5th abdominal segment to the 

 metathorax, there is difiiculty in accounting for the eight 

 abdominal segments exclusive of the genitalia, which are 

 present in the imago. 



