384 



ZOOLOGY. 



of concentrated salt water on railroad bridges in New En- 

 gland. Artemia fertilis Verrill abounds in Great Salt Lake. 



Rg. 245. — ThamnocepAaliis platyurus, male, natinal size, side and front view, a, 

 head of the female ; d, end of the body of the female, showing the ovisac. 



They may often be seen swimming about in pairs, as in 

 Fig. 248. This species has a Wauplius young like that of 



Fig. ^&,—Branchiiiectes Coloradensis Pack. 



the brine-shrimp of Europe (Fig. 244 b). It is a signifi- 

 cant fact, bearing on the question of the origin of species, 

 tha*, according to Schmankiewitsch, Artemia may change its 



