496 jMi'. p. R. Lowe — Observations 



development of variations on the two types, which, we may- 

 presume, originated on the South- American continent. Do 

 away with the islands, and we should be left (if we ignore 

 subspecific differences) with some four species to characterize 

 the genus. 



(10) The fact, perhaps less prominent than others, that 

 at the extreme northern limits of the genus (the Bahamas) 

 and again at the extreme southern (Peru and the province 

 of Rio Grande do Sul, Brazil) the tendency is to produce 

 species in which the individuals are characterized by larger 

 measurements than the rest and also by a more pallid 

 coloration. 



Absence of representatives from Cuba, Yucatan, and British 

 Honduras. — The fact that no species of Ca>reba inhabits Cuba, 

 and that not even stragglers, so far as I am aware, have been 

 recorded from that island, is an ornithological problem of 

 very peculiar interest. I have landed at some dozen widely- 

 separated localities, on the northern and southern coasts of 

 the island, where the local conditions seem to differ in no 

 obvious way whatever from those met with in other islands 

 where the genus is found, and yet have never seen so much 

 as a solitar}' straggler. 



From one's personal experience of the nature of the 

 surroundings, it seems impossible to believe that the Flora 

 can be in any way responsible for this absence. Moreover, 

 Dr. Rendle informs me that although the Flora of Cuba is 

 different in many respects from that of the rest of the 

 Greater Antillean islands, yet that such differences in his 

 opinion would be too insignificant to have any influence 

 on the subject in question. 



Climatic conditions might well have a more potent effect, 

 for in the winter months " northers " are frequent, and the 

 fall in temperature may be very marked. In this respect 

 Cuba appears to me to fall into the same category as the 

 more northern parts of Eastern Mexico and also of Florida. 

 Thus while the Flora of Cuba might remain almost identical 

 with that of other Greater Antillean islands (for we know 



