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A Sketch of the Structure and Development of the Eye 



of Clepsine. 



By 



C. 0. Whitman, 



Head Professor of Zoology, University of Chicago. 



A more complete account of the sense-organs will be published 

 in connection with papers devoted to American Clepsinidae, some of 

 which are now nearly completed. The results reached by one of 

 Prof. BüTSCHLi's pupils, Mr. B. L. Maier M, furnish some ground for 

 a brief preliminary sketch. 



Mr. Maier devotes considerable attention to the liner structure 

 of the „large clear cells", and their connection with nerve-fibres, 

 and concludes that they are visual cells, as I had before maintained ^). 

 He, however, fails to get a correct idea of the eye, and has the boldness 

 to dispute results which he might have easily verified. The author 

 fails to find „the tactile part of the organ", and so misses the 

 key to its morphology. That he should do this after the structure 

 had been pointed out, and while working under the guidance of an 

 experienced teacher, is hardly what we should expect from the Zoo- 

 logical Institute of Heidelberg. 



Although Maier finished his work in January 1892 — over two 

 years after the appearance of my paper — it seems that he worked 

 all that time without access to the facts published in the Journal ot 

 Morphology in April 1889, and only noticed them at last in a post- 



1) in: Zoolog. Jahrbücher, Bd. 5, Abth. f. Morph., p. 552, 1892. 



2) in: Journ. Morph., vol. 2, No. 3, 1889, and Biological Lectures, 

 1890, p. 50. 



