170 NATURAL SCIENCE [September 
but it is also used almost indiscriminately for any unusual fish. 
‘Sea-squirt’ is used for both ascidians and holothurians. When a 
native speaks of an ‘owl’ or a ‘ potoo, it is not always possible to 
determine whether he means the barn owl, or the large goatsucker, 
Nyctibius, as the names are constantly interchanged, ‘ Rain-bird’ 
may be a swift or one of three different kinds of cuckoo, while 
‘doctor-bird’ and ‘ banana-bird’ are also terms whose value depends 
on the speaker. 
That the fauna of Jamaica is undergoing comparatively rapid 
changes must be clear to even a casual observer. The manatee and 
the agouti, as well as the iguana, are apparently on the road to 
extinction, and it is almost certain that the famous ‘ Blue Mountain 
duck’ (Aestrelata caribbaea) has been exterminated during the last 
half of this century. The introduction of toads and the mongoose 
have clearly affected the land fauna, though it looks as if the native 
animals were adapting themselves to the new conditions. It is only 
a little over twenty-five years since the mongoose was introduced, 
and it is now common everywhere. Five or six years ago the 
snakes seemed to have been practically exterminated by their new 
enemy, but now they are beginning to appear again, so that one or 
two species are no longer varieties near Kingston, and we saw 
several near Port Antonio. Whether the snakes have developed 
some new form of defence or escape, or whether the mongoose has 
ceased to look for food in that group of reptiles, is still an open 
question. It is not only among the land animals, however, that 
such changes are going on. Several instances of remarkable 
changes in the abundance of a given species may be mentioned 
among marine animals. There seems to be very good evidence 
showing that the viviparous Synapta is becoming rarer each year, 
and that the area it inhabits is becoming more and more restricted. 
Cassiopea was far from common in 1896 where it was most 
abundant in 1893, and we did not find large numbers of it in any 
one place. The remarkable little cubomedusa, Zvripedalia, which 
was very abundant in the ‘Slashes’ in 1896 had completely dis- 
appeared in 1897, and a week of careful searching failed to disclose 
a single specimen anywhere in the Slashes or Lakes, It may not 
be safe to draw any sweeping conclusions from a few isolated facts 
of this sort, but they are at least worthy of note. 
One cannot close an account of zoological Jamaica without 
some reference to the scientific work which is being done in the 
island itself. As an authority on Jamaican shells, Henry Vendries, 
Esq., of Kingston, has a world-wide reputation, and his collection of 
native shells is very extensive. Mr P. W. Jarvis has been an 
extensive collector of the crabs of Jamaica, and has furnished the 
United States National Museum with the types of many new 
