May, 1922 WASTED ORNITHOLOGICAL MATERIAL 85 
and one-quarter pounds. A druggist’s beam balance was used in this portable 
combination; it will be seen from the accompanying illustration (fig. 31) that 
the pans, beam, weights and other parts are attached to the inner surface of 
one side of the box in such a manner as to be easily taken off. The assembled 
scales are set up on the beam post which is fastened to the center block, to 
which are also hinged each side of the box. The two box sides fall down onto 
the supporting surface (table, for instance), leaving the center block and beam. 
post in place. 
Such a combination can be used in the workshop as well as in the field, 
and with it much valuable information can be accumulated which probably is 
usually wasted. The age, sex, seasonal, and geographic variations in avian 
weights form a subject as yet almost untouched by the ornithologist; at least 
it so seems to the writer, who believes that it is not a routine act with most 
eollectors and preparators to determine and record the weight of a freshly 
Killed bird. The paucity of records of bird weights in literature seems to 
justify this belief. 
There is relatively little known concerning the body temperature of birds. 
That there is a more or less close relation between the temperature of a bird 
and the length of its incubaticn period seems indisputable to the writer. The 
exact delimitation of the relations between these two phenomena awaits solu- 
tion, at least until a large amount of data concerning avian body temperatures 
shall have heen gathered under known. approved. and carefully recorded con- 
ditions, and then studied and analvsed hand in hand with the equally eare- 
fully determined incubation period leneth of the corresponding bird. 
There are thousands and thousands of birds’ evgs preserved in our muse- 
ums and elsewhere. and. alone a few restricted lines. a study of them has been 
distinetly productive of advances in crnitholoev. Tt is highlv probable that 
the known weights of the eggs of different avian species does not inelude 
more than one nereent of the world’s hirds. For vears ornithologists have 
said that the differing Jengths of incubation amone birds is denendent on the 
differing sizes of their eggs. Jn the last analvsis. size of eegs. in this instance. 
means weicht of egos. How valuable can an explanation be which is based on 
less than one percent of the nossible data? 
From the viewnoint outlined bv there remarks. it would pnrobablv be ex- 
ceedinely discouraging if one were to know what the percentage of collected 
and preserved bird ‘‘stomachs’’ is t* the total number of birds annuallv eol- 
Jected for other purposes. It.seems quite unnecessarv to eall attention anew 
to the vast economic possibilities cnened un bv a seientifie study of the food 
of birds. a study which is best promoted bv investigating the ‘‘stomach’’ eon- 
tents of birds. The Biological Survev at Washineton weleomes all such mate- 
rial and disseminates for the benefit of all concerned the knowledge gained 
from it. 
The list of different possibilities for study in a freshlv killed bird has 
only been touched upon in the above remarks: manv more conld be enum- 
erated. all of surpassing interest. and manv with a chance of onenine un large 
fields of imnortant diseoverv. and original worth. The writer has felt for 
vears that such a waste of onvortunitv and material shonld not eontinue: not 
only because it is utterly unscientific. unnroductive. and inefficient. but also 
hecause many such opportunities, and much of such material may, in the fu- 
