Ll'TZ, LIST OF GREATER AXTILLEAX SPIDERS 



129 



per cent, for the Lesser Antilles, 41.2 per cent, for Hispaniola (practi- 

 cally, the port towns), 35.8 per cent, for Cuba and 33.3 per cent, for 

 Jamaica. 



Species also show the composite character of the Porto Eican spider 

 fauna and are perhaps more convincing than genera. Only 8.T per cent. 

 of the Porto Eican species are peculiar as contrasted with 52.4 per cent, 

 for the Lesser Antilles, 23.7 per cent, for Hispaniola, 25.2 per cent, for 

 Cuba and 48.9 per cent, for Jamaica. 



In view of this unusual chara/?ter of Porto Eican spiders, it is worth 

 while discussino: their distributicnal affinities. Table YTII o-ives the 

 dxta for the American distribution of species in a condensed form. 

 Table IX shows the percentages of the total number of species in the 

 several islands for various groupings. 



Table IX" 



Peculiar 



Not in other Antilles 



In other Antilles but not on mainland. 

 On maiDland but not in other Antilles. 

 On mainland (total) 



L. A. 



P. R. 



riisp. 



52.4 



8.7 



23.7 



72.0 



17.4 



37.0 



13.1 



29.0 



27.6 



19.6 



8.7 



13.^ 



34 . 5 



62.3 



48.7 



Cuba. 



25.2 

 56.5 

 13.7 

 31.3 

 61.1 



Jam. 



48 9 

 55.3 

 21.3 



6:4 



29. S 



Porto Eico has as high a mainland affinity as Cuba and liigher than 

 the other islands, but it has a lower direct affinity (a lower percentage 

 of species found on the mainland and not on the other Antilles) than 

 any except Jamaica. That is, its fauna is largely mainland species 

 which it has received by way of the other islands ; Cuba's species are also 

 largely mainland species, few of wliich have been passed on, while 

 Jamaica has few mainland species and most of these have been received 

 by way of the other islands or have been passed on to them. Of course, 

 it would be possible for a species to originate in a AVest Indian island 

 and then be transferred to the mainland and this may be true in Cuba. 

 It would be impossible to determine from the data A^ hether this has hap- 

 pened or not but it probably did not occur often enoug]i to seriously 

 complicate matters. 



The rest of Table IX agrees with the idea just stated and repeats what 

 was said before, as might be expected, since it is largely a complement of 

 the two lines jnst considered. Porto Eico has the smallest percentage of 

 endemic species of any of the islands or groups of islands; and, partly 

 tor this reason, but partly also because it has received a large proportion 



For explanation, see text. 



