Birds of Celebes: Psittacidae. 
169 
birds is extremely large and authorizes us to suppose that, what has been found 
till now from this period, only represents a very small part of the bird-life, 
already • very richly developed in those times. In the Miocene the similarity 
with the living fauna is further increased . . . and in some cases one can refer 
the fossil forms even to living genera . . . This similarity with the present 
time increases much more in the pliocene and quaternary times, when not only 
living genera but also recent species are represented . . . During tertiary 
times the present geographical distribution was regulated. Eocene and Miocene 
with their tropical and subtropical climate still offer in our latitudes birds, 
which now only live in the tropics or their nearest neighbourhood ... At 
the same time towards the end of the cretacious period and in the course of the 
Eocene and Miocene the continental separations and connections took place (e. g. the 
separation of Australia from the oriental region at the end of the cretacious pe- 
riod . . .), which . . . were of predominant influence on the distribution of birds.” 
The foregoing deductions show that there is no reason why the genus Lo~ 
riculus could not have existed from miocene times; by the argument it is assu- 
med that it existed when New Guinea was terrestially joined on to Asia, and 
ranged over this continent now broken up. The line of reasoning may then 
be as follows: There exists in all organic beings a tendency to develop in a 
certain direction, a tendency which is better able to assert itself under isolation. 
We have already been induced to draw the conclusion that the appearance of a 
similar red crown in L. indicus of Ceylon and L. apicalis of the Southern Phi- 
lippines, and the production of two considerably similar — but not nearly re- 
lated — birds in the adult males of L. stigmatus and L. honapartei, may be 
ascribed to a tendency to develop red on certain parts. Thus, under long 
separation L. stigmatus of Celebes may have become in virtue of this tendency 
from a beginning like L.vernalis first like L.pusillus of Java and have been 
changing ever since with time in a definite direction; L.pusillus, more recently 
isolated in Java, may have only reached its first simple stage of differentiation, 
but what L. stigmatus now is, or the like, L.pusillus may once become, so far 
at least as local influences allow. 
Such or a similar palaeogeographical explanation of the distribution of Lo- 
riculus meets, however, with many difficulties, which we abstain from detailing, 
as we here are on too hypothetical grounds. We have only wished to bring 
before the reader some proofs of our endeavours in searching for the truth, which 
perhaps future ornithologists studying this case will attain, where we end more 
or less with a query, though we are inclined to look on our first explauEition 
of the genesis of the species of the genus Loriculus as the most reasonable one. 
We bear, however, in mind, that the facts of geographical distribution and of 
variation of species are far too complicated to be mastered at the present time; 
much more knowledge than that of the present day is required to find the clue 
which will be satisfactory to the critical mind and the impartial judgment of 
the naturalist. 
Meyer & Wiglesworth, Birds of Celeties (Oct. 20th, 1897). 
22 
