A Sketch of the Structure and Development of the Eye of Clcpsine. 625 



the best ground is given for suspecting that the same economy has 

 been practised elsewhere. The discovery of these facts in the leeches, 

 led naturally to the anticipation of a similar origin for the eyes of 

 other Annelids, and in those groups that have had a common origin 

 with the Annelids, before all the Arthropods and Vertebrates. The 

 existence of segmental sense-organs, as I have said, is well known 

 in other Annelids than the leeches, and the origin of eyes from them 

 is fairly well indicated in many cases." 



Frnmmannsolie Biididnickerei (Hermann Pohle) in Jena. — HOC 



