44 Introduction: Migration. 
a host of fishes swam in front of it, while innumerable crabs sat upon it and 
sunned themselves”. 
In the special articles on the species records of individuals captured or 
observed at sea are quoted, such are: Tachyspizias soloensis (China Sea, near 
the Pescadores, May); Accipiter virgatus (China Sea, near the Natuna Is., 
14 tb j^ovember); Merops philippinus (Indian Ocean, November); Halcyon sancta 
(Pacific Ocean, 300 sea-miles S.E. of the Louisiade group); Hirundo rustica 
(several records from the seas between the Moluccas and S. China); Acrocephalus 
orientalis (40 miles N. of the Loochoo Islands); Motacilla flava (Indian Ocean and 
China Sea); Tringa rujicollis (China Sea, May 14^^); Hypotaenidia philippensis 
(Pacific Ocean far at sea east of Australia) ; Myristicivora hicolor and Caloenas nico~ 
harica (Seas of the East Indian Archipelago). 
Routes. — The above tables tend to prove that each species has 
its own route or routes of migration; nevertheless the species allow of 
a certain amount of co-ordination, as follows. 
From Northern Europe and Siberia to the East Indian A7-chipelago. — So far 
as species occurring in Celebes are concerned, migration reaches its highest 
development in the Arctic Chitfchaif, Phylloscopus borealis (J. H. Bias.) ahd the 
Siberian Pipit, Anthus gustavi Swinh. The former is known to breed as far 
west as Northern Norway (Collett), the latter as far as the Petchora (Seebohm 
and Har vie -Brown); they also breed in various parts of Siberia. In the 
winter there are no observations to show that individuals stop short of S.E. Asia 
and the East Indies; on the other hand they are observed to pass through China 
on migration, the Pipit holding to the countries washed by or near the Pacific 
Ocean and not visiting the Indian countries, while the Chitfchaff occurs both in 
the territories invaded by the Pipit and in Further India and the neighbouring- 
islands as well. So far as can be judged the general direction of the two 
species in autumn is from west to east across Siberia and then south or south- 
south-east. They are in singular contradiction to Gatke’s picturesque theory 
of an east to west flight at this season, and Anthus gustavi should be contrasted 
with Anthus I'ichardi V., which is supposed to migrate in the opposite direction, 
and is often referred to for proof by Gatke. 
Fi'om No7'thern Europe to Africa aiid from Siberia to the East Indies or 
further. — Many species migrate thus, but, as a rule, appreciable racial differ- 
ences may be seen in the western and eastern individuals, with intermediate 
forms from other localities between them. Such are: Hirundo 7'ustica, Cuculus 
canorus, Peti’ophila cyanus., Motacilla flava ^ Motacilla boarula^ Anthus cervinus^ 
Totanus calidi'is. Other forms are commonly separated as distinct species in the 
W est and East ; such are Charadrius pluvialis and fulvus., Acrocephalus turdoides and 
orientalis^ Tringa minuta and ruflcollis, Limosa lappoiiica and novaezealandiae.^ Numenius 
phaeopus and variegatus. Others do not differ in the West and East, or at least 
no prominent racial differences in them have as yet been insisted upon; such 
