8 The Ottawa Naturalist. 



evolutionary development. But in these Branchiopods we find a 

 further exemplification of development or evolution of a still more 

 extraordinary nature. Many intelligent minds remain in a state 

 of suspended judgment regarding the doctrine of evolution 

 because examples are not forthcoming of one kind of animal 

 actually becoming converted into another. Evolution to the 

 modern naturalist means, amongst other things, that old forms 

 of animals have actually changed into new and different forms. 

 The little creatures under consideration afford, perhaps, the most 

 striking illustration of the accomplishment of such a change. 

 Naturalists have long been familiar with one species, Attemia 

 salina L, which lives in salt-water. It can endure saltness so 

 extreme that in the famous salt pans at Lymington. Hampshire, 

 England, where the brine is so strongly charged with salt that 

 every other creature immersed in it is found to die, this delicate 

 shrimp-like crustacean abounds and flourishes. The workmen 

 call them Brine- worms, and they may be seen gliding on their 

 backs through the water, with their feet in constant motion, 

 ascending and descending, bending in endless curves, turning 

 over and over, wheeling to the right and to the left, and 

 apparently enjoying their brief term of active life. As is well 

 known, Schmankewitsch, by adding fresh-water to the salt- 

 water in which these creatures were living, succeeded, in the 

 course of several generations in transforming them into the fresh- 

 water species {Artenna niilhausenu). He also reversed the process 

 with similar success. His experiments have been much criticised 

 but it seems established that Schmankewitsch, at least, changed 

 one species of Phyllopod into another. The tail-lobes, in the two 

 species just named, are so different that no naturalist could 

 confuse them. In the freshwater species the lobe is strongly 

 bifid and provided with a thick bunch of setae or hairs, whereas 

 in the marine species {Arteviia salina) the lobe is 'rounded and 

 blunt, showing very slight bifidity, and the terminal hairs are 

 wholly absent. Moreover the gills, which are attached to the 

 swimming feet, differ very much in both species. But Schmanke- 

 witsch claimed that he did more, that he changed the fresh- 



