IN THE NORFOLK BROADS DISTRICT. 
61 
or what Darwin called “ Naturalists without souls,” and our 
knowledge of the time of duration in the imago state, the 
commonness or rarity, and the localisation of the species 
depends largely upon the casual observations made by these 
classes of collectors. How far such observations were 
accurate at the time they were made it is not possible now 
to say, but, after looking through records of collecting 
excursions published in the various entomological journals, 
inadequate observations seem to me exceedingly numerous. 
In the first place, a large number of such records leave out 
all reference to the commoner species, or I find such a remark 
as “ most of the species observed were (with one or two 
exceptions) similar to those found at Braemar,” * a statement 
which is of course utterly valueless. I think the insufficiency 
of the records results largely from the fact that most collectors 
pick up the species they want, and do not, at any rate on 
the spot, note down the species they see. 
Upon such imperfect material as this our catalogues of 
local faunas are to a great extent based, and such works are 
of less value from the fact that the time of year at which 
the species were observed is often only mentioned for the 
rarer kinds. No doubt the lists are fairly accurate as to the 
species present in the locality, but we require more careful 
observations as to the time of duration and commonness or 
rarity of each species, observations which are essential if 
we are to get any insight into the relationships between 
living things. 
As an example of the result of incomplete observations, 
I will refer to our Norfolk list of Coleoptera, compiled by 
Mr. Edwards, and published in our Transactions, Yols. V. and 
VI. I only refer, of course, to the Water Beetles, as I have 
only been studying that group. 
In this list I find Hydroporus erythroccphalus, L. described 
as “ common,” while H. planus , F. is described as “ very 
common.” In the Broads district during the past season, 
from March to November inclusive, the former species has 
* Coleoptera at Aviemore. G. C. Champion. Entom. Monthly Magazine, 
vol. xi. p. 64. 1874-5. 
