8 INTRODUCTION. 
with that view, employed various expert collectors, whose names are recorded in the 
body of the work, to visit special localities in Colombia, Ecuador, Peru, Guiana, and 
other places in South America. We continued to receive consignments from them for 
several years without having any idea of publishing a connected account of the results, 
and a very large amount of material, especially amongst the birds and insects, was thus 
accumulated. It was not till the year 1876 that it was suggested that the ‘ Biologia ’ 
should be undertaken, and three years later (September 1879) the first part appeared. 
In the meantime, various collectors were sent by us to Guatemala and other parts of 
Central America. 
Our method of publication was to bring out six quarto parts a year ; each part to 
contain twelve sheets made up of various subjects with six coloured plates, the plates and 
letterpress so numbered and paged that the parts might ultimately be broken up and 
bound together in their respective volumes when completed. In this way it was possible 
to keep several subjects in progress at once, and the plan answered well. We were, 
however, unable to adhere to the original scheme of completing the work in 60 parts, 
owing to the ever increasing amount of material received from our collectors—an 
amount so great that 215 Parts of Zoology alone have been required, the dates of 
issue extending over a period of 36 years. Even now some families of Insects, the 
Crustacea, &c., have not been dealt with—though this is chiefly attributable to the 
fact that no experts on these subjects were available. 
On arrival in England, the various consignments were opened, every specimen 
labelled with its exact locality, and the name of the collector attached. The animals 
sent were then sorted into their respective orders and families, and as occasion offered, 
handed over to specialists to be worked out. It was obviously impossible that we 
could undertake every subject, but the birds and the butterflies we set aside for our 
own share of the work. The names of the various authors who kindly helped us will 
be a sufficient indication of our good fortune in securing the services of so many 
eminent men, all of whom joined the enterprise with great spirit. 
In 1886, in company with Mr. H. J. Elwes, I visited Bombay, Simla, Delhi, Benares, 
Calcutta, and Darjeeling; thence crossing the Rungeet River by a swinging bamboo 
suspension bridge we entered native Sikkim, collecting plants, birds, and butterflies 
en route. At Darjeeling I purchased a large collection of butterflies, made by 
Lidderdale, which at the time was considered very representative of the Northern Indian 
fauna. Starting again from Darjeeling we made a second trip, this time on horse- 
back, travelling by the Government road constructed by Sir Richard Temple along 
the Nepaul ridge till we reached Falute (16,000 ft.), and there passed the night in 
a fairly comfortable bungalow. Next morning we witnessed a magnificent sunrise and 
obtained splendid views of Mounts Everest and Kinchinjunga rising from the mighty 
Himalayan range. I also visited Madras and Southern India and Ceylon before 
returning home. 
