320 THE ATLANTIC. [ CHAP. Iv. 
though the varieties are not so carefully selected as they are in 
Madeira. There are some fine trees of the Avocada pear (Per- 
sea gratissima), Which bear abundantly. The mango has been 
introduced into some gardens, but the crop can not be depended 
upon. The singular-looking papaw-trees (Carica papaya) are 
seen everywhere, male and female, round the cottages (Fig. 87) ; 
but the fruit is not much esteemed. 
The climate of Bermudas is very genial; the mean annual 
temperature is 21° C., while that of Madeira, in almost exactly 
the same latitude, is 18° C. This difference of 3° C.is due, 
partly to the prevalence at Bermudas of south-west winds blow- 
ing directly over the superheated reflux of the equatorial cur- 
rent, and partly to the position of the islands within the region 
of the banked-down warm water of the Gulf-stream. The tem- 
perature of the coldest month (17°2 C.) is, however, somewhat 
lower at Bermudas than at Madeira (17°:8 C.), while that of the 
warmest month is considerably higher (22° to 26° C.). This 
greater summer-heat, telling upon the flowering and the ripen- 
ing of the seeds of plants, gives the flora of Bermudas a more 
tropical character than that of Madeira; and this is undoubtedly 
increased by the circumstance that while the vegetation of Ma- 
deira and the other “ Atlantic islands,” the Acores and the Ca- 
naries, appears to be to a great degree an extension of that of 
Southern Europe, that of Bermudas, if we except a large num- 
ber of introduced plants, is in the main derived from the West 
Indies and the south of North America. 
The fauna of Bermudas is singularly poor. There are no 
wild mammals except the rats and mice which have been im- 
ported with foreign produce. Only about half a dozen land- 
birds breed on the islands, and all of these are common North 
American species; probably the most abundant and most wide- 
ly distributed are the American crow (Corvus Americanus) and 
a pretty quaker-colored little ground dove (Chamapelia passe- 
rina). Many American birds are annual visitors: we saw dur- 
