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Proceedings of the Royal Society of Edinburgh. [Sess. 
Part II. General Conclusions. 
(1) Chermes s. str. 
1. Two separate cycles have been proved to be present in Britain : 
(a) A cycle of two generations, Fundatrix and Gallicola non- 
migrans. The Fundatrix and Gallicola non-migrans lay 
yellow eggs on spruce, and the galls open over an extended 
period from the end of July until mid-September. This is 
the species Chermes abietis, Kalt., of Cholodkovsky. 
(b) A cycle of five generations, Fundatrix, Gallicola migrans, 
Colonici, Sexupara, and Sexuales. The Fundatrix lays green 
eggs on spruce, and the Gallicola migrans lays very dark 
green eggs on larch. The galls open during a limited period 
in the first half of August. This is the species Chermes viridis, 
Ratz., of Cholodkovsky. There is probably a cycle with both 
Gallicola migrans and non-migrans corresponding to Chermes 
abietis, L., Bonier, or Chermes occidentals , Choi. 
2. Sistens and progrediens larvae hatch from the eggs laid by the 
colonici. Many of the sistens larvae do not settle down on the bark, but 
migrate to the needles and die. 
(2) Cnaphalodes. 
3. Two separate cycles have been shown to be present in Britain : 
(a) A cycle of two generations, Fundatrix and Gallicola non- 
migrans. The latter lays bright orange-coloured eggs under 
the protection of copious “ wool.” The galls open over an 
extended period from the end of July until the end of 
September. This is the species Chermes lapponicus, Choi., 
var. tardus, Dreyfus, of Cholodkovsky. 
(b) A cycle of five generations, Fundatrix, Gallicola migrans, 
Colonici, Sexupara, and Sexuales. The Gallicola migrans 
lays dark bronze-coloured eggs without any “ wool ” covering 
on larch. The galls open during a limited period in the first 
half of July. This is the species Chermes strobilobius, Kalt., 
of Cholodkovsky. 
4. Sistens and progrediens larvse hatch from the eggs laid by the 
colonici and progredientes of Cnaplialodes strobilobius, Kalt. The relative 
proportion of each type is variable. 
It has thus been shown that the above cycles are not confined to North 
