Vol. xxxvi.] 54 



these circumstances, the students of Mallophaga in the 

 present connection have a very strong case already in their 

 favour. Then, diverting to the cases quoted where there 

 appears to be anomalous distribution, I favour the advocates 

 of convergence. When the parasites are more thoroughly 

 studied, it is certainly possible that the ones which now 

 look alike may prove to be very widely different. This is a 

 very common error^ as I believe these Mallophaga students 

 have commonly found. You continually get two micro- 

 scopic animals that superficially look alike^ but, when the 

 distinguishing features are recognised, prove very distinct. 

 With regard to the affinity of Apteryx to the Eails, this is 

 practically accepted by all osteologists at the present time. 



As to these apparent cases of relationship, it must be 

 always considered if we are dealing with an ancient class 

 of parasite, and we find them on widely divergent groups all 

 over the world, they may have established themselves on 

 these groups many centuries ago and continued on them, 

 and they would give no clue to the phylogeny of the birds. 

 I conclude the parasites will come into use when there is a 

 doubt about the systematic position of a genus, and after 

 considering the factors we get from the birds' skins. I 

 think such consideration will probably lead, in many cases, 

 to a better and more sound classification than we have at 

 present. 



Mr. Buxton : Is there any explanation of the fact that 

 some lice so very constantly trek on to a bird's head and 

 neck. If you skin a Capercallie, for instance, and perhaps 

 get three lice on your hands, and leave it until the evening, 

 you will find hundreds of Mallophaga all over the beak and 

 eyes and front parts of its head. One would like to know 

 if there is any explanation of it. Lice generally get into 

 the dark, but these things trek up into the light. 



Mr. Read asked if any particular species of parasite was- 

 found upon the Cuckoo, or whether it was liable to be 

 attacked by those which were commonly found upon those 

 species which acted as its foster-parents ; also whether the 

 House- Sparrow was ever attacked by parasites common to the 

 Swift, as the two species often occupied the same nesting-sites. 



