NATURE 
169 
THURSDAY, JUNE 22, 1899. 
THE EXPERIENCES OF A ZOOLOGIST IN 
AUSTRALASIA. 
In the Australian Bush, and on the Coast of the Coral 
Sea. being the Experiences and Observations of a 
Naturalist in Australia, New Guinea, and the 
Moluccas. By Richard Semon. With 86 illustrations 
and 4 maps. Pp. xv + 552. (London: Macmillan 
and Co., Ltd., 1899.) 
Je Oe have during the past few years reaped 
~ the benefit of Dr. Semon’s travels in Australasia 
and in the Malayan Archipelago in the beautifully illus- 
trated series of memoirs entitled “Semon, Zoologische 
Forschungsreisen in Australien und dem Malayishen 
Archipel,’ and published as part of the Jena Denk- 
schriften. Five quarto volumes have already been pub- 
lished, running to some 1600 pp. and 113 plates, many 
of which are coloured. They contain memoirs on 
Ceratodus, Monotremes, Marsupials, Manis, the Dugong 
and other vertebrates, as well as important communica- 
tions on various invertebrates ; most of these have been 
contributed by well-known European specialists, Dr. 
Semon himself being responsible for the monographs on 
the development of Ceratodus, and of the Monotremes 
and Marsupials. 
The large collections made by Dr. Semon having been 
carefully conserved, they have contributed considerably 
to our knowledge of tropical life from an anatomical as 
well as from a faunistic point of view. 
On glancing over this monumental series of memoirs 
one is struck by the amazing activity of Dr. Semon both 
in the field and in the laboratory, and all zoologists must 
once more feel grateful to Dr. Paul von Ritter for his 
princely liberality in the cause of science. 
But Dr. Semon has given us further cause for gratitude, 
as he has narrated his varied experiences of travel,and has 
recorded numerous observations on the habits of animals 
that would either have been unrecorded or buried in the 
obscurity of a technical treatise. More than this, Dr. 
Semon is not tainted with that half-cynical fiz-de-siécle 
spirit which is too rife at present even amongst scientific 
men. There are men who appear to be ashamed of the 
interest they take in their own work, and who freeze 
younger men with a smile. The author of “In the 
Australian Bush,” on the contrary, is not only a trained 
laboratory student, but he is a field naturalist as well. 
He revels in the varied aspects of nature, whether it be 
the monotonous Australian bush or a glorious tropical 
jungle, and he is not ashamed to let the reader share his 
joy and enthusiasm. 
Dr. Semon left Europe in the summer of 1891 (in the 
preface it is 1892) for the purpose of collecting embryo- 
logical material of the more interesting Australasian 
animals, and proceeded at once to the Burnett River; for 
it is only in the river systems of the Burnett and the 
Mary in South Queensland (latitude 25° to 26° S.) that 
the unique Ceratodus lives. This restriction of habitat 
is due to its avoidance of river heads, so that it cannot 
get conveyed by floods across a watershed ; its being 
easily affected by sea-water, so that migration through 
NO. 1547, VOL. 60] 
the mouths of streams is impracticable; and to the 
eggs being so frail and tender that they cannot bear 
the most transient drying. Its survival in the Burnett 
and Mary Rivers is probably owing to some particularly 
extensive water-holes ; should these ever dry up, this 
remarkable “living fossil” would become extinct. The 
fish is perfectly helpless out of the water, which it never 
leaves ; neither does it form a cocoon, or indulge in a 
summer sleep like its African cousin Protopterus. The 
lungs enable it, by respiring air, to exist in the dry season 
in water-holes that are crowded with refugees from the 
river, and which soon become putrid by rotting animal 
and vegetable substances. Dr. Semon was greatly hin- 
dered in his collecting of embryological material by heavy 
floods, so he returned the following season, and was re- 
warded by obtaining a complete series of eggs and 
larvee. 
Of the habits of the Platypus (Ornithorhynchus), and 
especially of the Echidna, we have several interesting 
observations. A considerable number of eggs and em- 
bryos were obtained, and as much adult material as 
Dr. Semon cared to preserve. As the book is not in- 
tended for specialists, the author gives only sufficient 
anatomical information to enable the reader to appreciate 
the importance of his investigations, and all through the 
book we have short expositions of local problems of the 
geographical distribution of animals, which should enable 
the non-scientific reader to appreciate the chief reason 
why field-naturalists make such large collections. 
Although most of Dr. Semon’s investigations were 
concerned with land animals, he did some marine work 
in the Moluccas, where he went on a fruitless quest for 
the eggs of the nautilus during the months of January 
and February (1893). When at Ambon (the Amboyna 
of the Portuguese) he found that the nautilus is very rarely 
caught during the north-west monsoon, but that it was 
not unfrequently found during the south-east trade-wind. 
Two other instances have been observed by Dr. Semon 
of a periodical migration of marine animals from deep 
to shallow water for the purpose of depositing their eggs. 
The first was at Heligoland, in the case of the common 
starfish (Astertas rudens) ; the second was at Ambon, 
where the brilliantly coloured, flexible sea-urchin (As- 
thenosoma urens) wanders into shallow water only during 
the south-east monsoon. Interesting observations are 
recorded of the means by which sea-urchins are pro- 
tected against the attack of certain rapacious marine 
snails that can spurt free sulphuric acid from their 
mouths in order to dissolve the calcareous spines and 
shells of these armoured echinoderms. 
The natives of the various countries which Dr. Semon 
visited also attracted his attention, and he has given us 
his impressions in a pleasant manner ; but he is less trust- 
worthy when he passes from his own observations to 
general statements. For example, he says, “by far the 
most of the Queensland and New South Wales tribes 
are entirely devoid of religion ” (p. 223). On the preced- 
ing page he asks, “ Can one speak of religion to a people 
whose language possesses hardly any words for abstract 
expressions, and who have no sort of worship for any 
supernatural being, idolatry, sacrifice, and prayer being 
things unknown throughout Australia?” Worship of a 
supreme being, idolatry, and sacrifice may be unknown 
I 
