THE GENERA AND SPECIES OF SYMPHYLA. 21 



V. On the Geographical Distribution. 



The euumeratiou ou p. 5 of the coinitries in which the 

 animals seen by me liave been captured is nearly exhaustive 

 as to our present knowledge of the distribution of the order ; 

 only the north-easterly part of the United States, North 

 Amei'ica, Mexico, and India must be added to the list 

 mentioned. But I venture to state that species of this group 

 can be captured in all countries of the world with exception 

 of the arctic and antarctic regions. I have examined twenty- 

 four species, which is six times as many as accepted by the 

 best authorities in the last sixteen years, but I am convinced 

 that nearly one hundred species, and perhaps a considerably 

 higher numbei-, are still undiscovered. The animals are easy 

 to collect, easy and cheap to preserve, the group is of high 

 systematic value, and our knowledge of its species has 

 hitherto been quite rudimentary. 



Under such circumstances it is impossible to say much on 

 the geographical distribution, and very few inferences of 

 tolerable certainty can be drawn. I have described twelve 

 species of each of the two old genera ; the genus Scutigerella 

 seems to be distributed a little nearer to the arctic and 

 antarctic regious than Scolopeudrella. But the species of 

 the last-named genus are generally smaller, and have, there- 

 fore, in all probability been more overlooked by most 

 collectors, and judging from this, and from the good result 

 as to new species of the same genus in my own excursions in 

 Calabria, I am inclined to believe that the genus Scolo- 

 peudrella contains considerably more species in warmer 

 regions than Scutigerella. 



Of several species of both genera I have examined 

 specimens from at least two and sometimes from three or 

 more localities rather distant from each other, but the 

 geographical distribution hitherto known of all species, with 

 the exception of Scutigeralla immaculata (Newp.), must 

 be regarded as moderately limited. Scolopeudrella vul- 



