2 26 PROBLEMS OF FERTILIZATION 



Tennent, David H. 



1910. ''Echinoderm Hybridization," Pub. No. ij2, Carne- 

 gie Institution, Washington (other references to same 

 author here). 



V^ERNON, H. M. 



1900. " Cross- Fertilization among the Echinoidea," Arch. 

 Jiir Entwickelungsmech., Band 9, p. 464. 

 Waldstein und Eckler. 



1 9 13. "Der Nachweis resorbierten Spermas in weiblichen 

 Organismus," Wiener klin. Wocheiischrifl, Jahrg. 26, 

 p. 1689. 

 Whitman, CO. 



1891. " Spermatophores as a Means of Hypodermic Im- 

 pregnation," Jour, of M or ph. y \o\. IV. 



