478 
MISCELLANEA. 
“ coloured corollas to serve as guides, and they are not, as far as I 
“ have seen, visited by insects. When insects are the agents of fer- 
“ tilization (and this is incomparably the more frequent case both 
“ with plants having separated sexes and with hermaphrodites), 
“ the wind plays no part, but we see an endless number of adap- 
“ tations to ensure the safe transport of the pollen by the living 
“ workers.” 
The other point refers to the fertilization of flowers in the bud. 
Mr. Darwin does not deny that such may take place. He says he 
has “ reason to believe that some flowers are frequently fertilized 
“ without expandingbut his observations lead him “ to disbelieve 
“ that this is ever the invariable course with all the flowers of any 
“ species whatever.” He concludes, “ Although good is gained by 
“ the inevitable crossing of the dimorphic flowers, yet numerous 
‘‘ other analogous facts lead me to conclude that some other quite 
‘ l unknown law of nature is here dimly indicated to us.” 
Philippi on the Metamorphoses oe Pteromalus. 
In the Annales des Sciences JSTaturelles, for 1851 (3rd Ser. V. xv.) 
Dr. Ph. de Philippi has given a very interesting account of the de¬ 
velopment of a small parasitic Hymenopterous insect belonging to 
the genus JPteromalus. This minute insect lays its eggs singly in the 
eggs of a beetle ( Hhynchites betuleti), which appear to be often so 
transparent, that the development of the Pteromalus-larva can be 
seen within them. Dr. Philippi found to his surprise that the 
animal hatched from the egg of the Pteromalus was u un tres petit 
“ animalcule, qu’on dirait un Infusoire muni d’une queue qu’il secoue 
“ brusquement comme un fouet, mais qui, par sa forme et les poils 
“ qui herissent son corps, ressemble a certaines levres de Dipteres.” 
Soon this curious larva lost its activity, and within it was developed 
a second larva, which after a while changed into a nymph. Dr. 
Philippi having satisfied himself that this was not a case of double 
parasitism, but that the first larva was really a stage in the develop¬ 
ment of the Pteromalus, came to the conclusion that it was the 
“ Grenerateur de la larve du Pteromalien, c’est, d’apres le mot adopte, 
suivant 1’exemple de M. Steenstrup, une nourrice .Quoi 
qu’il en soit, cet insecte nous ofire le seul exemple comiu, jusqu’ a 
present dans cette classe, d’une veritable generation par nourrices , ou, 
comme j’aimerais mieux l’appeler, empruntant une phrase du lan- 
gage politique, d’une generation a deux degree. ’ ’ Dr. Philippi now 
confirms (Hote Zoologiche estratti dall’ Archivio per la Zbologia, 
Anatomia, e Pisiologia, mese di Griugno, 1862 ?) his previous obser¬ 
vations in most particulars, but regards it not as a case of meta¬ 
genesis, but of hypermetamorphosis. In other words he considers 
that the first larva passes into the second by a change of skin, as in 
Sitaris , Meloe , and other insects, and we think that most naturalists 
will be disposed to acquiesce in this rectification. J. L. 
