10 NATURE 
interlaced, are amply discussed. Good maps help to 
make these difficult problems easier to understand. 
In the last chapter Adm. Phaff gives a description 
of the coast lines of the East Indian Isles. 
In his preface Dr. W. v. d. Stok states that only new 
and very costly expeditions will be able to bring new 
light on the subjects treated in this volume, so we must 
therefore be glad to possess such an excellent summary 
of our knowledge of the East Indian Seas. 
W. G. N. VAN DER SLEEN. 

For the Diffusion of Knowledge. 
Annual Report of the Board of Regents of the Smithsonian 
Institution, showing the Operations, Expenditures, and 
Condition of the Institution for the Year ending June 
30, 1920. (Washington: Government Printing 
Office, 1922.) 
F the 704 pages that make up the volume before 
us, 550, accompanied by 230 plates, are 
assigned to the appendix. The body of the report is 
somewhat dead by now, but the large tail is still lively 
enough to attract attention. It consists, as usual, of 
papers general in character and ranging over the field 
of human intellect from astronomy to fine art. There 
are 27 such papers, of which 14 are original and by 
Americans, and 13 are reprints or translations of 
articles by American, British, and French authors. 
All are examples of popularisation of a high type, and 
many of them could be understood by readers with 
little or no previous knowledge of the subject. The 
names of H. H. Turner, W. D. Halliburton, M. Caullery, 
and Auguste Lameere among the foreign authors indi- 
cate the general excellence. The papers that appear 
here for the first time are, to a large extent, summaries 
of work that has been published elsewhere, but some 
of them contain matter that seems to be fresh. 
Dr. N. E. McIndoo’s article on the senses of insects 
may serve for example. After discussing the nature 
of insect vision by the simple and the compound eyes, 
he proceeds to the sense of smell, and considers it first 
as a means of recognition. In insects that sense is far 
more developed than in man, yet Dr. McIndoo found 
that by smell alone he could distinguish the three 
castes of bees as well as other components of the hive. 
It is probable that each individual bee has its peculiar 
odour, but the combination of all these that makes up 
the hive odour is regarded as the most important, as 
indeed the ruling power in a colony. It “is a means 
of preserving the social life of the bees from without, 
and the queen odour which is a part of it insures con- 
tinuation of the social life within. The workers ‘ know’ 
their hive-mates by the odour they carry. This insures 
NO. 2775, VOL. III] 
[JANUARY 6, 1923 

harmony and a united defence against attack. The 
queen odour constantly informs the workers that their 
queen is present. Even though shesdoes not rule, her 
presence means everything to the bees in perpetuating 
the colony. Thus, by obeying the stimuli of the hive 
odour and queen odour, and being guided by instinct, 
a colony of bees perhaps could not want a better ruler.” 
Among ants the same broad principles hold, but here 
the family odour retains its importance. 
What then are the organs by which insects recognise 
these odours? Dr. McIndoo has identified them as 
small pores scattered or grouped on the body and 
appendages. A nerve ends in each pore, and the 
opening is often protected by a hair. By covering the 
pores, experimental proof of their olfactory function 
was obtained. 
That bees, among other insects, can discriminate 
between foods is well known, and that their power of 
discrimination exceeds that of man was experimentally 
proved by Dr. McIndoo. He ascribes this power, 
however, not to taste, but to smell. Taste and smell 
are closely allied, and it is possible that the only 
difference lies in the organs that respond, the stimulus 
itself being identical. In bees there appear to be no 
such organs connected with the alimentary tract, so 
that the discrimination is probably by smell. 
Passing over the sense of touch, we find some novel 
remarks on the sense of hearing, and an interpretation 
of certain organs on the antenne (pore-plates and 
Johnston’s organ) as possibly auditory in function, 
though the audition can, in that event, be little more 
than an exaggerated sense of touch. 
Whether there are in insects or in any other animals 
senses of a nature entirely hidden from us, is a question 
raised by Mr. H. H. Beck in an article on ‘“‘ The Occult 
Senses in Birds ” (reprinted from the Auk). In some 
species of moth, for instance, a female exposed but 
invisible will soon attract the males of the species. 
Various explanations of this have been suggested— 
from Mr. Beck’s “‘ mate-finding sense” to wireless 
telegraphy, but Dr. McIndoo believes that the highly 
developed sense of smell is enough to account for it. 
The same faculty surely renders it unnecessary to 
postulate, with Mr. Beck, a special “ food-finding 
sense,” though his story of vultures from eight miles 
away spotting a freshly-killed dog at the bottom of a 
sink-hole is certainly uncanny. Then there is the 
homing sense—the most puzzling of all; but it seems 
less rational to demand some mysterious force, as 
Bethe does, than to suppose the exercise of the usual 
senses more highly developed than a townsman can 
ever imagine, used simply or in combination, con- 
sciously or unconsciously. 
One might pass on to consider some curious instincts 
ee 
