INTRODUCTION.
THIS work was originally intended to be confined to a description of the Zoological
Results of the two Yunnan Expeditions. In working them out, however,
I was led to examine certain Asiatic genera as a whole; and having done so, I
have embraced the opportunity, to incorporate these observations along with the
results of the Expeditions, as they were founded, in the m ajority of cases, on the
actual comparison of the types of the individual species; hence the descriptions of
the various species of Eylobates, Macacus, Sewmopithecus, Scwrm, 8fC.
In the same way, in dealing with the Cetacean of the Irawady, I was led to
compare it with its near ally occasionally found in the estuary streams of the
Ganges, and, as this latter form had never been fully described, to include an account
of its placentation and anatomy generally alongside of the former. Moreover, as
both of these Cetaceans are more or less fluviatile in their habits, I was further
induced, from the circumstance tha t I had already devoted some time to an examination
of the placentation and anatomy of Platamsta, to add a history of its distribution
and structure to th a t of the two former, and thus to give a Monograph of
the known fluviatile Cetacea of Asia.
I t will be observed th a t for special sections of the work I am indebted to
naturalists who are recognized authorities in the departments which they describe.
I t is necessary th a t I should here give a short account of the two Expeditions,
in order to bring out the difficulties with which I was beset as a naturalist, and
which, to my great regret, were of so formidable a nature, th a t they restricted my
investigations within the narrowest limits in a country the fauna of which is
extremely rich and all b u t unknown.
The Eirst Expedition was despatched in the end of 1867 from Calcutta, and
returned in November 1868; and the Second Expedition left Mandalay on the
3rd January 1875, and returned thither on the 10th March of the same year.
By the permission of the Trustees of the Indian Museum, my services were
placed a t the disposal of the Government of India to accompany the two Missions as
Naturalist and Medical Officer.
With regard to the scope of the Eirst Expedition, it was intended th a t it should
penetrate from Mandalay into the Province of Yunnan, vid Bham6, and, if possible.