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irides, weight, and colours, all duly entered in the diary. Colours 

 should be noted as early as possible. Mandibles and irides, and 

 the feet in a lesser degree fade rapidly. Birds have not got black 

 beads for eyes as is commonly supposed, the majority have hazel 

 brown irides. 



Data Tickets. 



Every bird should have a label. The least important part of which 

 is the name of the bird. The bird can almost always speak for itself 

 on this point and difficulties of determination are less pronounced 

 in the Aves than in the Insecta. There are fewer species, and ex- 

 cept in a few instances they are well marked, they are not subject 

 to distinct seasonal forms, although seasonal changes of plumage 

 occur. On the other hand locality and date are all important. If 

 possible give the contents of the stomach. A serial number is also 

 given to each bird and recorded in the same margin of the diary. 



For the sake of convenience we are now instituting a loose 

 leaf record, under which we shall place all the information and 

 references to the bird which we come across, together with all 

 measurements of eggs and birds. This will be in addition to the 

 day to day record in the diary, and will enafjle us to keep all such 

 notes as we may possess relating to any one bird in one place for 

 direct access. 



Eggs. 



Remembering what I said about the taking of clutches only, 

 likewise note that cuckoo's eggs should be kept with the clutch of 

 the bird in whose nest the cuckoo deposited its eggs. The egg 

 label should show the following details : — Order, family, sub- 

 family, genus and species, and if you like the trivial name of the 

 bird to which the eggs belong. It should also show on the reverse 

 side of the label the locality whence the eggs came, the name of the 

 collector, date, the clutch mark, the original number of the clutch , 

 the state of incubation, identity, the structure, composition and 

 situation of the nest. 



To take these in their order, the locality, the name of the 

 collector and date, do not call for any particular remark after what 

 Z said above. 



The Clutch Mark. 



This should consist of a serial number with any addition you 

 may wish to make. In practice we use a letter for each successive 

 year, and a number, e.g., F. 22, this is the 22nd clutch of the oth 

 year since we commenced. The only virtue in it is that it prevents 

 the serial number running into more than three figures, as the 

 occasions upon which you are likely to exceed 999 clutches in any 

 one year will be exceedingly rare. Eggs are too delicate to write 

 localities on. All clutch marks to be in waterproof indelible ink. 



The original number of clutch should be given, i.e., whether 5, 

 6, or 20, because one ought then to know the usual number laid 



