and Classification of Rhynchota. 239 
de l'existence de stigmates thoraciques ” (p. 245). With re- 
gard to the abdominal spiracles he specifies his general state- 
ment thus, that the common number is six, but that Miris and 
Capsus have seven pairs. He mentions this as ^ un trait ana- 
tomique fort remarquable" (p. 243); but he considers it still 
more remarkable that the female of Coreus (Syromastes) mar- 
genatus (L.) has seven pairs, whilst the male has only six; and 
in treating of the lateral part of the last abdominal segment of 
the female, he exclaims :—“ Mais ce qu'il y a de fort remarqua- 
ble dans ce repli, c'est qu'il est stigmatifére : en sorte que la 
femelle de cet insecte a une paire de stigmates de plus que le 
mile” (p. 206). In Nepa he finds abdominal stigmata only 
in the third and fifth segments—that is, three pairs in all be- 
sides the respiratory tubes, which he considers morphologically 
separate organs, “‘ indépendant des segmens propres de l'abdo- 
men ” (p. 246). 
Against these statements concerning Nepa, Burmeister ob- 
serves (Handb. d. Ent. ii. p.197) that, with regard to the thorax, 
he cannot fully endorse them, because he has found a pair o 
Spiracles between the metanotum and the first dorsal segment 
ofthe abdomen, It escaped Burmeister’s attention that Léon 
Dufour had both described (p. 256) and figured (fig. 196, e) this 
organ, although he had refused to put it in a line with the or- 
mary spiracles and described it as a “ sachet utriculaire.” 
For the rest, Burmeister justly observes that, as these animals 
fly, they must have spiracles on the thorax ; and he modestly 
adds that, inasmuch as it is well known how very difficult it 1s 
to observe these, they might exist in Nepa, although so able 
an anatomist as Léon Dufour had been unable to find them. 
Burmeister himself had several years before (Handb. d. Ent. 
1. p. 174) indicated the existence of a pair of spiracles between 
the prothorax and mesothorax in Rhynchota; and it seems 
