of certain species of Willow. — Port 2nd. 281 



This so-called 1st abdominal joint in TenthreeHnidee and Uroceridxis 

 manifestly homologous with the posterior subsegment of what is 

 generally considered as the inetathorax in other Hymenoptera; and 

 Latreille, Audouin and Schaum, believing that it was abdominal, main- 

 tained that therefore the two were both of them abdominal and not 

 thoracic, while Westwood rightly, in ray opinion, contended that both 

 were thoracic. In a recent Paper {Proc. B. S. i\ r . H. 1866, pp. 279 

 — 295) Dr. Packard, although he endorses Westwood's theory on this 

 matter, (p. 282.) asserts that during the development of the pupa of 

 Bombus from the larva, and before the final moulting of the larval in- 

 tegument " the basal ring of the abdomen is plainly seen to be trans- 

 ferred from the abdomen to the thorax." (p. 282.)* He might as 

 well assert that, during the process of pulling off a fine network glove 

 from the hand of a lady, the fingers are plainly seen to be transferred 

 to the palm of the hand. Because the metathorax of the future pupa 

 is seen, through the transparent integument of the larva, to underlie at 

 this particular time the basal ring of the larval abdomen, it by no 

 means follows that the former originates and is developed from the 

 latter. Dr. Packard himself allows, that at this particular time the 

 head of the future pupa underlies conjointly the head and the 1st 

 thoracic segment of the larva ; (p. 280 ;) yet he fully agrees with West- 

 wood in repudiating the inference drawn therefrom by Dr. Ratzeburg, 

 that the head of the pupa is formed conjointly out of the head and the 

 1st thoracic segment of the larva, (p. 280, note.) Surely, if such 

 proof is good for nothing in the one case, it ought to be good for no- 

 thing in the other case as well. But then, if Dr. Packard had been 

 consistent in his reasoning here, he would have missed what he con- 

 siders a notable exemplification of Prof. Dana's theory of cephalization. 

 (pp. 282 and 286.) Unfortunately, however, he cannot be consistent 

 with himself, even for a dozen consecutive pages. On page 283 he 

 says, that the moult into the pupa state takes place in what he calls 

 the 3rd stage ; on page 295 he says, that it takes place in what he calls 

 the 2nd stage. It evidently takes place in passing from his so-called 1st 

 stage to his so-called 2nd stage; and the 1st stage of what he calls the 

 semi-pupa, (^fig. 1, Packard.) is the larva, and the stages 2 — 4 (figs. 2 

 — -i, Packard) are the pupa, in gradually progressive stages of develop- 

 ment; and all his voluminous distinctions between the semi-pupa and 

 pupa states, and the dogmatic assertion (p. 286) that "the terms larva, 

 pupa and imago are not absolute terms," are merely darkening coun- 



* See also Proc. etc. VI. p. 44, where the same doctrines are re-asserted. 



