The differences between Tenthredo and Allantiis are very 

 slight; the 3rd joint of the antennae is evidently longer than 

 the 4th in the latter genus, which seems to be the essential 

 character. Tenthredo comprises 23 British species, of which 

 I shall notice a few in my own cabinet. 

 2. cingulata Fab.— Curt. Brit. Ent. pi. 692. 



The remarkable insect figured is a hermaphrodite, the right- 

 hand half being feminine, that on the left masculine, so that 

 in the specimen the antennae, abdomen, legs, and wings are 

 not symmetrical : the sexual organs are representeil at fig. 6. 

 Since the attention of naturalists has been called to this sub- 

 ject, a large number of insects of this description have been 

 discovered, especially amongst the Papilionidae. I have on 

 a former occasion alluded to an example oi Smerinthus Pop7ili 

 in my possession, but the most extraordinary specimen that 

 has come under my observation was a North American 

 Lucanus, which Mr. Raddon showed me. Never having seen 

 any other Hymenopterous insect of this kind, I have been in- 

 duced to figure the Tenthredo in the annexed plate; and as 

 the sexes vary in the colour and markings of the abdomen, &c., 

 they are rendered conspicuous in the figure. I took this indi- 

 vidual with a vast number of i'emales off Fern in the New 

 Forest in June; the males were very rare. I have also found 

 the females in Coomb Wood in May. 



13. neglecta St. Farg. Man. 77. 229. — subinterrupta Steph. 

 Middle of June, Yorkshire and Scotland, J. C. 



14. ornata St. Farg. p. 77. no. 228. — Faun. Fran. pi. S.f. 5. 



16. scutellaris Fab.? Panz. 98. 12. 

 Common in June and July. 



17. ambigua Klug. die Blaft. p. 202. 146. 



18. nassata Linn.— Panz. 65. 2. S- — Tiliae Panz. 91. 13. ?. 

 End of May and June, abundant in hedges. 



19. Rubi? Panz. 91. 14. ? . 



Beginning of August near Manchester, and at Roundstone 

 in Connemara. 

 21. antennata Klug. p. 129. 98.— duplex Geoff.l 



Beginning of June, Glanville's Wootton, Mr. Dale. 

 23. Rapae Zvm«. — Schccf. lcon.pl. 179. 1. 



May and June, common in hedges. 

 6. dimidiata Fab. The lower recurrent nervure in this species, 

 nearly meets the second in the submarginal cell, as in fig. 9*. 

 Klug considers T. dimidiata., scutellaris, nassata and Tilice of 

 Panzer to be one species, which he has named instabilis; but 

 as the neuration of the wings is so different in T. dimidiata, I 

 think that at least must be distinct. 



Mr. Dale possesses a specimen with seven legs. 



The Plant is Spergula arvensis^ Corn Spurry. 



