These insects are so very similar to the Chironomi, especially 

 the females, that it is very difficult to separate them. B}' com- 

 paring the wing in our plate with that of Chironomus in pi. 90, 

 amongst other differences it will be seen that in one there 

 are 4, in the other 3 nervures springing from the apex of the 

 discoidal cell, the joints of the antennte are also very dissimilar, 

 which is useful in distinguishing the females, but they are fre- 

 quently very difficult to detect in the males. Meigen describes 

 the antennae as 14-jointed from his not including the basal 

 joint. 



The following species have been detected in Britain. 



1. varius Fab. — Meig. tab. '2,. f. 12 ^. Female middle of 



April, Lisson Gi'ove. 



2. nebulosus Meig. — Curt. Brit. JEnt. j^l 501 c^. Beginning 



of May, Regent's Park and Coombe-wood ; male middle 

 of October, Isle of Wight. 



3. punctatus Fab. — 4. notatus Meig. — 27- flabellicornis Meig. 



6. 260. 27. — 5. melanurus Meig. 



6. zonains Fab. — Taken at Oxford. — 7^. laetus? Meig. 



7. monilis Linn. — maculata DcG. 6. tab. 27. f. 15 — 19. 



Middle of June, walls near Ambleside; August, Gardens, 

 Scotland; female beginning of September, Durnford, 

 Wilts. 



8. punctipennis Meig. — cinctus Panz. 105. 6. May, June, 



August and September, marshy places, Mr. Samouelle. 



9. praecox Meig. — 10 choreus Meig. — Scotland. — 11. culici- 



formis Linn. July. — 12. nervosus Hoff. — 13. ferrugi- 

 nicollis Meg. — 14. pallidulus Meg. — 15. melanops Wied. 

 — 16. Arundineti Linn. — 17. carneus Fab. — 23. lentigi- 

 nosus Fries'^ — 24. albipes Fries? 

 30. nigrimanus Meig. 6. 261. 30. — May and beginning of 

 June on a post by a river in the New Forest; end of 

 July, several on paling near Hampton Court. 



The Plant is Aristolochia Clematitis (Common Birth wort), 

 communicated by the Honourable C. A. Harris and the Rev. 

 P. Hansell from Godstone Nunnery near Oxford. Mr. W. 

 Baxter of the Botanic Garden, called my attention to a curious 

 fact in the oeconomy of this plant; he pointed out to me a mi- 

 nute black Gnat inclosed in the globular base of the flowei', 

 which it enters, and being confined there brushes the pollen 

 upon the stigma, and impregnates it. For want of specimens 

 I have not been able to ascertain the species of the insect, 

 which I at first took for a Tanypus: it nearly resembled 

 the Chironomus occultans Meig., but it may possibly be a 

 Ceratopogon. 



