destroyers have escaped, for these again have their parasites 

 as we learn from Geoffroy, who states that a Cynips destroys 

 the larvae of the Ichneumon des Peucerons (Aphidius), and 

 from his description I think it may be my Ceraphron Carpen- 

 teri (folio 249* No. 10), which I there stated had been bred 

 from the Aphides by the late Mr. Carpenter. 



I am indebted to Mr. Haliday for a valuable monograph 

 containing 19 species of Aphidii ; and Mr. F. Walker tells me 

 he thinks he has about 50. It being therefore impossible to 

 give specific characters of the whole, I shall avail myself of 

 Mr. Haliday's paper, and give his admirable divisions. 



* Wings with 3 cubital areolets (Div. 1. Nees). Radial areolet termi- 

 nating at the apex. Head small, rather globose. Antennse shorter than 

 the body of 11 joints in both sexes. Aculeus short compressed, a little 

 curved upwards. 



* * Wings with one cubital cell effuse to the margin, distinct from the 

 anterior of the disc (Div. 3. Nees). Wings very ample, the radial areolet 

 effuse, including the whole apex. Antennae and legs long and extremely slen- 

 der. Head small globular narrowed to the back. Palpi long and slender. 



Mr. Haliday has described 4 species of the first division, 

 and 3 of this, but has given no names, and I have none of them. 



* * * Wings with the anterior cell of the disc and inner cubital confluent 

 and sometimes both together open to the margin (Div. 2. Nees). Head 

 more transverse than in the other divisions. Radial cell terminating at 

 the apex, its interior nervure often vanishing before the apex. 



a. Valves of the aculeus compressed, straight or curved upwards, black 

 (Antennae longer in the males, varying in the number of joints, more nu- 

 merous in the same sex : middle cell complete or open only to the exterior 

 cubital one). 



This division contains A. Pini Hal., the males taken on 

 the larch in Aug. the females on the Finns sylvestris in Sept. 

 — infulatus Hal. on the larch in Aug. — pictus Curt, on the 

 Scotch fir, Sept. — dimidiatus Curt. — Rosae, Hal.? — picipes 

 Nees, infests the Aphides of Hieracium ? — fumatus Hal. 



b. Valves of the aculeus incurved, broad, generally securiform, pale, 

 f Anus beneath unarmed. 



1. The middle areolet defined posteriorly. 

 Contains two unnamed species. 



2. The middle areolet entirely eftuse to the margin (species very minute). 

 Contains two species, and probably A. basalis Curtis^s Guide. 

 ft Anus beneath in female armed with 2 diverging horns recurved at 



the end, longer than the aculeus which lies between them. Middle areolet 

 effuse. Antennae in the females of 1 1 joints, rather thicker towards the apex. 

 Contains A. letifer .H«Z.^ — A. minutus Curt. — A. constrictus 

 Hal., and another. 



The insect figured may be the I. Aphidum Linn.: but as 

 the specific name has been converted into one for the genus 

 by Nees ab Esenbeck, I have given it the name of ' Cirsii ' 

 from its being said to be parasitic on the Aphis Cirsii, so 

 named from its inhabiting Cirsium arvense Lam., the Carduus 

 arvensis of this Work, PI. 296. 



The Plant figured \s Anemone aj^ennina (Mountain Anemone) 

 from Lord Spencer's park, communicated by W. Christy, Esq- 



